diff --git a/CLAUDE.md b/CLAUDE.md
index 6e1984d..a86f18f 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1073,4 +1073,320 @@ Chapter Progress: 11% (100/909 points)
 
 ---
 
+## 🔒 STRICT INTERFACE SYSTEM - C++ Style Contracts
+
+### 🎯 Philosophy: Contract-Driven Architecture
+
+**Like C++ header files (.h)**, we enforce strict interfaces that MUST be implemented. Any missing method = **RED SCREEN ERROR** at startup.
+
+### 📦 Interface Hierarchy
+
+```
+StrictInterface (base)
+├── ProgressItemInterface           # For progress tracking items
+│   ├── VocabularyDiscoveryItem
+│   ├── VocabularyMasteryItem
+│   └── ContentProgressItems (Phrase, Dialog, Text, etc.)
+│
+├── ProgressSystemInterface         # For progress systems
+│   ├── ProgressTracker
+│   └── PrerequisiteEngine
+│
+└── DRSExerciseInterface           # For exercise modules
+    ├── VocabularyModule
+    ├── TextAnalysisModule
+    ├── GrammarAnalysisModule
+    ├── TranslationModule
+    └── OpenResponseModule
+```
+
+### 🏗️ 1. **StrictInterface** (Base Class)
+
+**Location**: `src/DRS/interfaces/StrictInterface.js`
+
+**Purpose**: Ultra-strict base class with visual error enforcement
+
+**Features**:
+- ✅ Validates implementation at construction
+- ✅ Full-screen red error overlay if method missing
+- ✅ Sound alert in dev mode
+- ✅ Screen shake animation
+- ✅ Impossible to ignore - forces correct implementation
+
+**Error Display**:
+```
+┌─────────────────────────────────────────────┐
+│                                             │
+│           🔥 FATAL ERROR 🔥                │
+│                                             │
+│      Implementation Missing                 │
+│                                             │
+│  Class: VocabularyModule                   │
+│  Missing Method: validate()                │
+│                                             │
+│  ❌ MUST implement all interface methods   │
+│                                             │
+│     [ DISMISS (Fix Required!) ]            │
+│                                             │
+└─────────────────────────────────────────────┘
+```
+
+### 🎯 2. **ProgressItemInterface**
+
+**Location**: `src/DRS/interfaces/ProgressItemInterface.js`
+
+**Purpose**: Contract for all progress tracking items
+
+**Required Methods** (4):
+```javascript
+validate()           // Validate item data
+serialize()          // Convert to JSON
+getWeight()          // Return item weight for progress calculation
+canComplete(state)   // Check prerequisites
+```
+
+**Implementations**:
+- VocabularyDiscoveryItem (1pt)
+- VocabularyMasteryItem (1pt)
+- PhraseItem (6pts)
+- DialogItem (12pts)
+- TextItem (15pts)
+- AudioItem (12pts)
+- ImageItem (6pts)
+- GrammarItem (6pts)
+
+### 🔧 3. **ProgressSystemInterface**
+
+**Location**: `src/DRS/interfaces/ProgressSystemInterface.js`
+
+**Purpose**: Contract for all progress management systems
+
+**Required Methods** (17):
+
+**Vocabulary Tracking:**
+- `markWordDiscovered(word, metadata)`
+- `markWordMastered(word, metadata)`
+- `isWordDiscovered(word)`
+- `isWordMastered(word)`
+
+**Content Tracking:**
+- `markPhraseCompleted(id, metadata)`
+- `markDialogCompleted(id, metadata)`
+- `markTextCompleted(id, metadata)`
+- `markAudioCompleted(id, metadata)`
+- `markImageCompleted(id, metadata)`
+- `markGrammarCompleted(id, metadata)`
+
+**Prerequisites:**
+- `canComplete(itemType, itemId, context)`
+
+**Progress:**
+- `getProgress(chapterId)`
+
+**Persistence:**
+- `saveProgress(bookId, chapterId)`
+- `loadProgress(bookId, chapterId)`
+
+**Utility:**
+- `reset(bookId, chapterId)`
+
+**Implementations**:
+- ProgressTracker - Weight-based progress with items
+- PrerequisiteEngine - Prerequisite checking and mastery tracking
+
+### 🎮 4. **DRSExerciseInterface**
+
+**Location**: `src/DRS/interfaces/DRSExerciseInterface.js`
+
+**Purpose**: Contract for all DRS exercise modules
+
+**Required Methods** (10):
+
+**Lifecycle:**
+- `init(config, content)` - Initialize exercise
+- `render(container)` - Render UI
+- `destroy()` - Clean up
+
+**Exercise Logic:**
+- `validate(userAnswer)` - Validate answer, return { isCorrect, score, feedback, explanation }
+- `getResults()` - Return { score, attempts, timeSpent, completed, details }
+- `handleUserInput(event, data)` - Handle user input
+
+**Progress Tracking:**
+- `markCompleted(results)` - Mark as completed
+- `getProgress()` - Return { percentage, currentStep, totalSteps, itemsCompleted, itemsTotal }
+
+**Metadata:**
+- `getExerciseType()` - Return exercise type string
+- `getExerciseConfig()` - Return { type, difficulty, estimatedTime, prerequisites, metadata }
+
+**Implementations**:
+- VocabularyModule - Flashcard spaced repetition
+- TextAnalysisModule - AI-powered text comprehension
+- GrammarAnalysisModule - AI grammar correction
+- TranslationModule - AI translation validation
+- OpenResponseModule - Free-form AI evaluation
+
+### ✅ 5. **ImplementationValidator**
+
+**Location**: `src/DRS/services/ImplementationValidator.js`
+
+**Purpose**: Validate ALL implementations at application startup
+
+**Validation Phases**:
+
+```javascript
+🔍 VALIDATING DRS IMPLEMENTATIONS...
+
+📦 PART 1: Validating Progress Items...
+  ✅ VocabularyDiscoveryItem - OK
+  ✅ VocabularyMasteryItem - OK
+  ✅ PhraseItem - OK
+  ✅ DialogItem - OK
+  ✅ TextItem - OK
+  ✅ AudioItem - OK
+  ✅ ImageItem - OK
+  ✅ GrammarItem - OK
+
+🔧 PART 2: Validating Progress Systems...
+  ✅ ProgressTracker - OK
+  ✅ PrerequisiteEngine - OK
+
+🎮 PART 3: Validating DRS Exercise Modules...
+  ✅ VocabularyModule - OK
+  ✅ TextAnalysisModule - OK
+  ✅ GrammarAnalysisModule - OK
+  ✅ TranslationModule - OK
+  ✅ OpenResponseModule - OK
+
+✅ ALL DRS IMPLEMENTATIONS VALID
+```
+
+**If ANY validation fails**:
+- 🔴 Full-screen red error
+- 🚫 Application REFUSES to start
+- 📋 Clear error message with missing method name
+- 🔊 Alert sound (dev mode)
+- 📳 Screen shake
+
+### 🎯 Integration with Application.js
+
+**At Startup** (lines 55-62):
+```javascript
+// Validate all progress item implementations (STRICT MODE)
+console.log('🔍 Validating progress item implementations...');
+const { default: ImplementationValidator } = await import('./DRS/services/ImplementationValidator.js');
+const isValid = await ImplementationValidator.validateAll();
+
+if (!isValid) {
+    throw new Error('❌ Implementation validation failed - check console for details');
+}
+```
+
+### 📋 Creating New Implementations
+
+#### **New Progress Item**:
+```javascript
+import ProgressItemInterface from '../interfaces/ProgressItemInterface.js';
+
+class MyCustomItem extends ProgressItemInterface {
+    constructor(id, metadata) {
+        super('my-custom-item', id, metadata);
+    }
+
+    validate() {
+        // MUST implement
+        if (!this.metadata.required) {
+            throw new Error('Missing required data');
+        }
+        return true;
+    }
+
+    serialize() {
+        // MUST implement
+        return {
+            ...this._getBaseSerialization(),
+            customData: this.metadata.custom
+        };
+    }
+
+    getWeight() {
+        // MUST implement
+        return ProgressItemInterface.WEIGHTS['my-custom-item'] || 5;
+    }
+
+    canComplete(userProgress) {
+        // MUST implement
+        return true; // Check prerequisites here
+    }
+}
+```
+
+#### **New Progress System**:
+```javascript
+import ProgressSystemInterface from '../interfaces/ProgressSystemInterface.js';
+
+class MyProgressSystem extends ProgressSystemInterface {
+    constructor() {
+        super('MyProgressSystem');
+    }
+
+    // MUST implement all 17 required methods
+    async markWordDiscovered(word, metadata = {}) { /* ... */ }
+    async markWordMastered(word, metadata = {}) { /* ... */ }
+    isWordDiscovered(word) { /* ... */ }
+    isWordMastered(word) { /* ... */ }
+    // ... 13 more methods
+}
+```
+
+#### **New Exercise Module**:
+```javascript
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
+
+class MyExerciseModule extends DRSExerciseInterface {
+    constructor() {
+        super('MyExerciseModule');
+    }
+
+    // MUST implement all 10 required methods
+    async init(config, content) { /* ... */ }
+    async render(container) { /* ... */ }
+    async destroy() { /* ... */ }
+    async validate(userAnswer) { /* ... */ }
+    getResults() { /* ... */ }
+    handleUserInput(event, data) { /* ... */ }
+    async markCompleted(results) { /* ... */ }
+    getProgress() { /* ... */ }
+    getExerciseType() { return 'my-exercise'; }
+    getExerciseConfig() { /* ... */ }
+}
+```
+
+### 🚨 Enforcement Rules
+
+**NON-NEGOTIABLE**:
+1. ❌ **Missing method** → RED SCREEN ERROR → App refuses to start
+2. ❌ **Wrong signature** → Runtime error on call
+3. ❌ **Wrong return format** → Runtime error on usage
+4. ✅ **All methods implemented** → App starts normally
+
+**Validation happens**:
+- ✅ At application startup (before any UI renders)
+- ✅ On module registration
+- ✅ At interface instantiation
+
+**Benefits**:
+- 🛡️ **Impossible to forget implementation** - Visual error forces fix
+- 📋 **Self-documenting** - Interface defines exact contract
+- 🔒 **Type safety** - Like TypeScript interfaces but enforced at runtime
+- 🧪 **Testable** - Can mock interfaces for unit tests
+- 🔄 **Maintainable** - Adding new method = update interface + all implementations get errors
+
+---
+
+**Status**: ✅ **INTERFACE SYSTEM IMPLEMENTED**
+
+---
+
 **This is a high-quality, maintainable system built for educational software that will scale.**
\ No newline at end of file
diff --git a/DRS_IMPLEMENTATION_PLAN.md b/DRS_IMPLEMENTATION_PLAN.md
new file mode 100644
index 0000000..057b371
--- /dev/null
+++ b/DRS_IMPLEMENTATION_PLAN.md
@@ -0,0 +1,575 @@
+# 📋 DRS EXERCISE MODULES - IMPLEMENTATION PLAN
+
+**Goal**: Réimplémenter tous les modules DRS pour respecter `DRSExerciseInterface`
+
+**Status**: 🔴 0/11 modules conformes
+
+---
+
+## 📊 ÉTAT DES LIEUX - 11 Modules Existants
+
+### ✅ Modules AI (Score-Based) - 5 modules
+Utilisent l'IA pour validation et scoring (0-100 points)
+
+1. **TextAnalysisModule** - Analyse de texte avec AI
+2. **GrammarAnalysisModule** - Correction grammaticale AI
+3. **TranslationModule** - Traduction validée par AI
+4. **OpenResponseModule** - Réponse libre évaluée par AI
+5. **AudioModule** - Analyse audio avec transcription
+
+### 🎯 Modules Locaux (Non-AI) - 6 modules
+Validation locale sans IA
+
+6. **VocabularyModule** - Flashcards spaced repetition
+7. **WordDiscoveryModule** - Découverte passive de vocabulaire
+8. **PhraseModule** - Pratique de phrases
+9. **GrammarModule** - Exercices de grammaire structurés
+10. **TextModule** - Lecture et compréhension de textes
+11. **ImageModule** - Description d'images
+
+---
+
+## 🎯 INTERFACE STRICTE - 10 Méthodes Requises
+
+Chaque module DOIT implémenter:
+
+### **Lifecycle** (3 méthodes)
+```javascript
+async init(config, content)      // Initialize module
+async render(container)           // Render UI
+async destroy()                   // Cleanup
+```
+
+### **Exercise Logic** (3 méthodes)
+```javascript
+async validate(userAnswer)        // Returns { isCorrect, score, feedback, explanation }
+getResults()                      // Returns { score, attempts, timeSpent, completed, details }
+handleUserInput(event, data)      // Handle user interactions
+```
+
+### **Progress Tracking** (2 méthodes)
+```javascript
+async markCompleted(results)      // Mark as completed + save progress
+getProgress()                     // Returns { percentage, currentStep, totalSteps, itemsCompleted, itemsTotal }
+```
+
+### **Metadata** (2 méthodes)
+```javascript
+getExerciseType()                 // Returns type string
+getExerciseConfig()               // Returns { type, difficulty, estimatedTime, prerequisites, metadata }
+```
+
+---
+
+## 📈 ANALYSE PAR MODULE
+
+### 1️⃣ **VocabularyModule** (43KB)
+**État**: 🟡 Partiel (3/10 méthodes)
+
+**Existant**:
+- ✅ `async init()` - Ligne 47
+- ✅ `async validate(userInput, context)` - Ligne 169
+- ✅ `getProgress()` - Ligne 220
+
+**Manquant**:
+- ❌ `async render(container)` - Logique UI dispersée, pas de méthode centralisée
+- ❌ `async destroy()` - Pas de cleanup formel
+- ❌ `getResults()` - Résultats calculés à la volée, pas de méthode dédiée
+- ❌ `handleUserInput(event, data)` - Géré inline dans render
+- ❌ `async markCompleted(results)` - Sauvegarde dispersée
+- ❌ `getExerciseType()` - Type non formalisé
+- ❌ `getExerciseConfig()` - Config non structurée
+
+**Priorité**: 🔥 **HAUTE** (module principal, bien structuré)
+
+---
+
+### 2️⃣ **TextAnalysisModule** (24KB)
+**État**: 🟡 Partiel (2/10 méthodes)
+
+**Existant**:
+- ✅ `async validate(userInput, context)` - Ligne 127 (AI validation)
+- ✅ `getProgress()` - Ligne 204
+
+**Manquant**:
+- ❌ `async init(config, content)` - Pas d'init formelle
+- ❌ `async render(container)` - UI dispersée
+- ❌ `async destroy()` - Pas de cleanup
+- ❌ `getResults()` - Résultats inline
+- ❌ `handleUserInput(event, data)` - Pas formalisé
+- ❌ `async markCompleted(results)` - Pas formalisé
+- ❌ `getExerciseType()` - Manque
+- ❌ `getExerciseConfig()` - Manque
+
+**Priorité**: 🔥 **HAUTE** (AI module, pattern pour autres)
+
+---
+
+### 3️⃣ **GrammarAnalysisModule** (26KB)
+**État**: 🟡 Partiel (2/10 méthodes)
+
+**Existant**:
+- ✅ `async validate(userInput, context)` - AI correction
+- ✅ `getProgress()` - Basique
+
+**Manquant**: Mêmes que TextAnalysisModule
+
+**Priorité**: 🔶 **MOYENNE** (similaire à TextAnalysis)
+
+---
+
+### 4️⃣ **TranslationModule** (30KB)
+**État**: 🟡 Partiel (2/10 méthodes)
+
+**Existant**:
+- ✅ `async validate(userInput, context)` - AI translation check
+- ✅ `getProgress()` - Basique
+
+**Manquant**: Mêmes que TextAnalysisModule
+
+**Priorité**: 🔶 **MOYENNE** (AI module standard)
+
+---
+
+### 5️⃣ **OpenResponseModule** (21KB)
+**État**: 🟡 Partiel (2/10 méthodes)
+
+**Existant**:
+- ✅ `async validate(userInput, context)` - AI evaluation
+- ✅ `getProgress()` - Basique
+
+**Manquant**: Mêmes que TextAnalysisModule
+
+**Priorité**: 🔶 **MOYENNE** (AI module générique)
+
+---
+
+### 6️⃣ **WordDiscoveryModule** (11KB)
+**État**: 🟡 Partiel (1/10 méthodes)
+
+**Existant**:
+- ✅ `async init()` - Basique
+
+**Manquant**: Presque tout
+
+**Priorité**: 🟢 **BASSE** (va fusionner avec VocabularyModule)
+
+---
+
+### 7️⃣ **PhraseModule** (31KB)
+**État**: 🟡 Partiel (2/10 méthodes)
+
+**Existant**:
+- ✅ `async validate()` - Local validation
+- ✅ `getProgress()` - Basique
+
+**Manquant**: 8 méthodes
+
+**Priorité**: 🔶 **MOYENNE** (local validation, pattern différent)
+
+---
+
+### 8️⃣ **GrammarModule** (74KB)
+**État**: 🔴 Ancien (code legacy volumineux)
+
+**Existant**: Code legacy, structure différente
+
+**Priorité**: 🟢 **BASSE** (peut être remplacé par GrammarAnalysisModule)
+
+---
+
+### 9️⃣ **TextModule** (52KB)
+**État**: 🔴 Ancien (code legacy)
+
+**Existant**: Code legacy, structure différente
+
+**Priorité**: 🟢 **BASSE** (peut être remplacé par TextAnalysisModule)
+
+---
+
+### 🔟 **AudioModule** (68KB)
+**État**: 🟡 Partiel
+
+**Existant**:
+- ✅ `async validate()` - Audio analysis
+
+**Priorité**: 🔶 **MOYENNE** (module spécialisé)
+
+---
+
+### 1️⃣1️⃣ **ImageModule** (69KB)
+**État**: 🟡 Partiel
+
+**Existant**:
+- ✅ `async validate()` - Image analysis
+
+**Priorité**: 🔶 **MOYENNE** (module spécialisé)
+
+---
+
+## 🗺️ ROADMAP D'IMPLÉMENTATION
+
+### 🎯 **PHASE 1 - Modules Prioritaires** (2 modules)
+
+#### **1.1 VocabularyModule** ⭐ PRIORITÉ #1
+**Pourquoi**: Module le plus utilisé, bien structuré, pas d'IA
+
+**Tâches**:
+1. ✅ Garder `init()`, `validate()`, `getProgress()` existants
+2. 🔨 Extraire logique UI dans `render(container)`
+3. 🔨 Créer `destroy()` pour cleanup
+4. 🔨 Créer `getResults()` pour statistiques finales
+5. 🔨 Créer `handleUserInput(event, data)` pour boutons
+6. 🔨 Créer `markCompleted(results)` pour sauvegarde
+7. 🔨 Créer `getExerciseType()` → `'vocabulary'`
+8. 🔨 Créer `getExerciseConfig()` avec difficulty, time, etc.
+
+**Estimation**: 2-3 heures
+
+---
+
+#### **1.2 TextAnalysisModule** ⭐ PRIORITÉ #2
+**Pourquoi**: Module AI de référence, pattern pour tous les modules AI
+
+**Tâches**:
+1. ✅ Garder `validate()` et `getProgress()` existants
+2. 🔨 Créer `init(config, content)` pour setup
+3. 🔨 Créer `render(container)` pour UI
+4. 🔨 Créer `destroy()` pour cleanup
+5. 🔨 Créer `getResults()` avec AI score + metadata
+6. 🔨 Créer `handleUserInput(event, data)`
+7. 🔨 Créer `markCompleted(results)`
+8. 🔨 Créer `getExerciseType()` → `'text-analysis'`
+9. 🔨 Créer `getExerciseConfig()`
+
+**Estimation**: 2-3 heures
+
+---
+
+### 🔄 **PHASE 2 - Modules AI** (3 modules)
+
+**Pattern**: Copier structure de TextAnalysisModule, adapter validation
+
+#### **2.1 GrammarAnalysisModule**
+- Utiliser pattern de TextAnalysisModule
+- Adapter `validate()` pour grammar checking
+- **Estimation**: 1-2 heures
+
+#### **2.2 TranslationModule**
+- Utiliser pattern de TextAnalysisModule
+- Adapter `validate()` pour translation
+- **Estimation**: 1-2 heures
+
+#### **2.3 OpenResponseModule**
+- Utiliser pattern de TextAnalysisModule
+- Adapter `validate()` pour open responses
+- **Estimation**: 1-2 heures
+
+---
+
+### 📦 **PHASE 3 - Modules Locaux** (2 modules)
+
+#### **3.1 PhraseModule**
+- Utiliser pattern de VocabularyModule
+- Validation locale (pas d'AI)
+- **Estimation**: 1-2 heures
+
+#### **3.2 Fusionner WordDiscoveryModule**
+- Intégrer dans VocabularyModule (discovery mode)
+- Supprimer module séparé
+- **Estimation**: 1 heure
+
+---
+
+### 🎨 **PHASE 4 - Modules Spécialisés** (2 modules)
+
+#### **4.1 AudioModule**
+- Audio player + transcription
+- AI analysis similaire TextAnalysisModule
+- **Estimation**: 2-3 heures
+
+#### **4.2 ImageModule**
+- Image display + zoom
+- AI vision analysis
+- **Estimation**: 2-3 heures
+
+---
+
+### 🗑️ **PHASE 5 - Cleanup Legacy** (2 modules)
+
+#### **5.1 Supprimer GrammarModule**
+- Remplacé par GrammarAnalysisModule (AI)
+- Archiver code si besoin
+
+#### **5.2 Supprimer TextModule**
+- Remplacé par TextAnalysisModule (AI)
+- Archiver code si besoin
+
+---
+
+## 🛠️ STRATÉGIE D'IMPLÉMENTATION
+
+### **Pattern 1: AI Modules** (TextAnalysis, Grammar, Translation, OpenResponse, Audio, Image)
+
+```javascript
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
+
+class ModuleName extends DRSExerciseInterface {
+    constructor() {
+        super('ModuleName');
+        this.config = null;
+        this.content = null;
+        this.container = null;
+        this.startTime = null;
+        this.attempts = 0;
+        this.currentScore = 0;
+    }
+
+    async init(config, content) {
+        this.config = config;
+        this.content = content;
+        this.startTime = Date.now();
+    }
+
+    async render(container) {
+        this.container = container;
+        // Render UI logic here
+    }
+
+    async destroy() {
+        if (this.container) {
+            this.container.innerHTML = '';
+            this.container = null;
+        }
+    }
+
+    async validate(userAnswer) {
+        this.attempts++;
+        // AI validation logic
+        return {
+            isCorrect: true/false,
+            score: 0-100,
+            feedback: '...',
+            explanation: '...',
+            metadata: {}
+        };
+    }
+
+    getResults() {
+        return {
+            score: this.currentScore,
+            attempts: this.attempts,
+            timeSpent: Date.now() - this.startTime,
+            completed: this.currentScore >= 70,
+            details: { /* exercise-specific */ }
+        };
+    }
+
+    handleUserInput(event, data) {
+        // Handle button clicks, input changes, etc.
+    }
+
+    async markCompleted(results) {
+        // Save to progress system
+    }
+
+    getProgress() {
+        return {
+            percentage: 100, // or calculate based on steps
+            currentStep: 1,
+            totalSteps: 1,
+            itemsCompleted: this.currentScore >= 70 ? 1 : 0,
+            itemsTotal: 1
+        };
+    }
+
+    getExerciseType() {
+        return 'module-type';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: this.config
+        };
+    }
+}
+```
+
+### **Pattern 2: Local Modules** (Vocabulary, Phrase)
+
+```javascript
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
+
+class ModuleName extends DRSExerciseInterface {
+    constructor() {
+        super('ModuleName');
+        this.items = [];
+        this.currentIndex = 0;
+        this.results = [];
+    }
+
+    async init(config, content) {
+        this.config = config;
+        this.items = content.items; // Extract items
+        this.startTime = Date.now();
+    }
+
+    async render(container) {
+        this.container = container;
+        this._renderCurrentItem();
+    }
+
+    async destroy() {
+        this.container.innerHTML = '';
+        this.container = null;
+    }
+
+    async validate(userAnswer) {
+        // Local validation (no AI)
+        const isCorrect = userAnswer === this.items[this.currentIndex].answer;
+        this.results.push({ isCorrect, answer: userAnswer });
+
+        return {
+            isCorrect,
+            score: isCorrect ? 100 : 0,
+            feedback: isCorrect ? 'Correct!' : 'Incorrect',
+            explanation: '...',
+            metadata: {}
+        };
+    }
+
+    getResults() {
+        const correctCount = this.results.filter(r => r.isCorrect).length;
+        const score = Math.round((correctCount / this.results.length) * 100);
+
+        return {
+            score,
+            attempts: this.results.length,
+            timeSpent: Date.now() - this.startTime,
+            completed: this.currentIndex >= this.items.length,
+            details: { correctCount, totalCount: this.items.length }
+        };
+    }
+
+    handleUserInput(event, data) {
+        // Handle next/previous/answer buttons
+    }
+
+    async markCompleted(results) {
+        // Save progress
+    }
+
+    getProgress() {
+        return {
+            percentage: Math.round((this.currentIndex / this.items.length) * 100),
+            currentStep: this.currentIndex + 1,
+            totalSteps: this.items.length,
+            itemsCompleted: this.results.filter(r => r.isCorrect).length,
+            itemsTotal: this.items.length
+        };
+    }
+
+    getExerciseType() {
+        return 'module-type';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: 'easy',
+            estimatedTime: this.items.length * 0.5,
+            prerequisites: [],
+            metadata: this.config
+        };
+    }
+}
+```
+
+---
+
+## ✅ CHECKLIST DE VALIDATION
+
+Pour chaque module réimplémenté:
+
+### **Implémentation**
+- [ ] Hérite de `DRSExerciseInterface`
+- [ ] Implémente les 10 méthodes requises
+- [ ] Méthodes retournent le bon format
+- [ ] Pas d'erreur au startup (validation stricte)
+
+### **Lifecycle**
+- [ ] `init()` initialise correctement config et content
+- [ ] `render()` crée l'UI dans le container
+- [ ] `destroy()` nettoie proprement (remove listeners, clear DOM)
+
+### **Exercise Logic**
+- [ ] `validate()` retourne `{ isCorrect, score, feedback, explanation }`
+- [ ] `getResults()` retourne stats complètes
+- [ ] `handleUserInput()` gère tous les events
+
+### **Progress**
+- [ ] `markCompleted()` sauvegarde dans ProgressTracker
+- [ ] `getProgress()` retourne progression en temps réel
+
+### **Metadata**
+- [ ] `getExerciseType()` retourne string unique
+- [ ] `getExerciseConfig()` retourne config complète
+
+### **Testing**
+- [ ] Module se charge sans erreur
+- [ ] UI s'affiche correctement
+- [ ] Validation fonctionne (AI ou local)
+- [ ] Progress se sauvegarde
+- [ ] Cleanup fonctionne (pas de memory leak)
+
+---
+
+## 📊 ESTIMATION TOTALE
+
+| Phase | Modules | Temps Estimé |
+|-------|---------|--------------|
+| Phase 1 | 2 (Vocabulary, TextAnalysis) | 4-6h |
+| Phase 2 | 3 (Grammar, Translation, OpenResponse) | 3-6h |
+| Phase 3 | 2 (Phrase, WordDiscovery fusion) | 2-3h |
+| Phase 4 | 2 (Audio, Image) | 4-6h |
+| Phase 5 | 2 (Cleanup legacy) | 1h |
+| **TOTAL** | **11 modules** | **14-22h** |
+
+---
+
+## 🎯 ORDRE DE PRIORITÉ
+
+1. 🔥 **VocabularyModule** - Module principal, pas d'AI, bien structuré
+2. 🔥 **TextAnalysisModule** - Template pour tous modules AI
+3. 🔶 **GrammarAnalysisModule** - Copie pattern TextAnalysis
+4. 🔶 **TranslationModule** - Copie pattern TextAnalysis
+5. 🔶 **OpenResponseModule** - Copie pattern TextAnalysis
+6. 🔶 **PhraseModule** - Local validation, copie pattern Vocabulary
+7. 🔶 **AudioModule** - Spécialisé, similaire TextAnalysis
+8. 🔶 **ImageModule** - Spécialisé, similaire TextAnalysis
+9. 🟢 **WordDiscoveryModule** - Fusionner dans Vocabulary
+10. 🟢 **GrammarModule (legacy)** - Supprimer/archiver
+11. 🟢 **TextModule (legacy)** - Supprimer/archiver
+
+---
+
+## 🚀 PROCHAINES ÉTAPES
+
+### **Immédiat** (à faire maintenant):
+1. Valider ce plan d'implémentation
+2. Commencer par **VocabularyModule** (priorité #1)
+3. Une fois validé, dupliquer pattern pour autres modules
+
+### **Validation Plan**:
+- ❓ Plan approuvé ?
+- ❓ Ordre de priorité correct ?
+- ❓ Temps estimé réaliste ?
+- ❓ Pattern de code acceptable ?
+
+---
+
+**Status**: 📝 **PLAN PRÊT - AWAITING APPROVAL**
diff --git a/src/DRS/exercise-modules/AudioModule.js b/src/DRS/exercise-modules/AudioModule.js
index c00019c..52ebb78 100644
--- a/src/DRS/exercise-modules/AudioModule.js
+++ b/src/DRS/exercise-modules/AudioModule.js
@@ -3,11 +3,11 @@
  * Handles audio passages with listening questions and pronunciation practice
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class AudioModule extends ExerciseModuleInterface {
+class AudioModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('AudioModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -1879,6 +1879,71 @@ Format: [answer]yes/no [explanation]your comprehensive educational feedback here
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('AudioModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'audio',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'audio' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'audio';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default AudioModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/GrammarAnalysisModule.js b/src/DRS/exercise-modules/GrammarAnalysisModule.js
index 5bf14cd..7a8fe1f 100644
--- a/src/DRS/exercise-modules/GrammarAnalysisModule.js
+++ b/src/DRS/exercise-modules/GrammarAnalysisModule.js
@@ -1,13 +1,14 @@
 /**
  * GrammarAnalysisModule - Open grammar correction with AI feedback
  * Presents grammar exercises with open correction fields, validates using real AI
+ * Implements DRSExerciseInterface for strict contract enforcement
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class GrammarAnalysisModule extends ExerciseModuleInterface {
+class GrammarAnalysisModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('GrammarAnalysisModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -697,6 +698,82 @@ Return ONLY valid JSON:
 
         setTimeout(() => errorDiv.remove(), 5000);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('GrammarAnalysisModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup();
+    }
+
+    getResults() {
+        const totalSentences = this.currentSentences.length;
+        const correctedSentences = this.userCorrections.length;
+        const correctSentences = this.progress.sentencesCorrect;
+        const score = totalSentences > 0 ? Math.round((correctSentences / totalSentences) * 100) : 0;
+
+        return {
+            score,
+            attempts: correctedSentences,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: correctedSentences >= totalSentences,
+            details: {
+                totalSentences,
+                correctedSentences,
+                correctSentences,
+                accuracy: this.progress.averageAccuracy,
+                grammarRulesLearned: Array.from(this.progress.grammarRulesLearned),
+                corrections: this.userCorrections
+            }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event && event.type === 'input') this._handleInputChange?.(event);
+        if (event && event.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'grammar-analysis',
+                subtype: 'completion',
+                content: { sentences: this.currentSentences },
+                userResponse: this.userCorrections,
+                validation: { score, accuracy: details.accuracy, grammarRulesLearned: details.grammarRulesLearned },
+                context: { moduleType: 'grammar-analysis', totalSentences: details.totalSentences }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'grammar-analysis';
+    }
+
+    getExerciseConfig() {
+        const sentenceCount = this.currentSentences ? this.currentSentences.length : this.config.sentencesPerExercise;
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: sentenceCount * 2, // 2 min per sentence
+            prerequisites: [],
+            metadata: { ...this.config, sentenceCount, requiresAI: true, model: this.config.model }
+        };
+    }
 }
 
 export default GrammarAnalysisModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/GrammarModule.js b/src/DRS/exercise-modules/GrammarModule.js
index 72c29e1..7c732b7 100644
--- a/src/DRS/exercise-modules/GrammarModule.js
+++ b/src/DRS/exercise-modules/GrammarModule.js
@@ -3,11 +3,11 @@
  * Handles grammar rules, sentence construction, and correction exercises
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class GrammarModule extends ExerciseModuleInterface {
+class GrammarModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('GrammarModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -2055,6 +2055,71 @@ Format: [answer]yes/no [explanation]your comprehensive grammar analysis here`;
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('GrammarModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'grammar',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'grammar' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'grammar';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default GrammarModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/ImageModule.js b/src/DRS/exercise-modules/ImageModule.js
index 2c5d0ab..cbb8af8 100644
--- a/src/DRS/exercise-modules/ImageModule.js
+++ b/src/DRS/exercise-modules/ImageModule.js
@@ -3,11 +3,11 @@
  * Handles image content with visual analysis questions and description exercises
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class ImageModule extends ExerciseModuleInterface {
+class ImageModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('ImageModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -1944,6 +1944,71 @@ Format: [answer]yes/no [explanation]your comprehensive educational feedback here
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('ImageModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'image',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'image' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'image';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default ImageModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/OpenResponseModule.js b/src/DRS/exercise-modules/OpenResponseModule.js
index 62d7fd5..1d5263c 100644
--- a/src/DRS/exercise-modules/OpenResponseModule.js
+++ b/src/DRS/exercise-modules/OpenResponseModule.js
@@ -1,13 +1,14 @@
 /**
  * OpenResponseModule - Free-form open response exercises with AI validation
  * Allows students to write free-text responses that are evaluated by AI
+ * Implements DRSExerciseInterface for strict contract enforcement
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class OpenResponseModule extends ExerciseModuleInterface {
+class OpenResponseModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('OpenResponseModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -607,6 +608,81 @@ Format your response as:
         const previousTotal = this.progress.averageScore * (this.progress.questionsAnswered - 1);
         this.progress.averageScore = (previousTotal + result.score) / this.progress.questionsAnswered;
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('OpenResponseModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        const totalQuestions = this.questions ? this.questions.length : 0;
+        const answeredQuestions = this.userResponses ? this.userResponses.length : 0;
+        const score = this.progress ? Math.round(this.progress.averageScore * 100) : 0;
+
+        return {
+            score,
+            attempts: answeredQuestions,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: answeredQuestions >= totalQuestions,
+            details: {
+                totalQuestions,
+                answeredQuestions,
+                averageScore: this.progress?.averageScore || 0,
+                responses: this.userResponses || []
+            }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event && event.type === 'input') this._handleInputChange?.(event);
+        if (event && event.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'open-response',
+                subtype: 'completion',
+                content: { questions: this.questions },
+                userResponse: this.userResponses,
+                validation: { score, averageScore: details.averageScore },
+                context: { moduleType: 'open-response', totalQuestions: details.totalQuestions }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'open-response';
+    }
+
+    getExerciseConfig() {
+        const questionCount = this.questions ? this.questions.length : this.config?.questionsPerExercise || 2;
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: questionCount * 3, // 3 min per question
+            prerequisites: [],
+            metadata: { ...this.config, questionCount, requiresAI: true }
+        };
+    }
 }
 
 export default OpenResponseModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/PhraseModule.js b/src/DRS/exercise-modules/PhraseModule.js
index a635070..2bd1c85 100644
--- a/src/DRS/exercise-modules/PhraseModule.js
+++ b/src/DRS/exercise-modules/PhraseModule.js
@@ -3,11 +3,11 @@
  * Uses GPT-4-mini only, no fallbacks, structured response format
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class PhraseModule extends ExerciseModuleInterface {
+class PhraseModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('PhraseModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -910,6 +910,71 @@ Format: [answer]yes/no [explanation]your detailed feedback here`;
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('PhraseModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'phrase',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'phrase' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'phrase';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default PhraseModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/TextAnalysisModule.js b/src/DRS/exercise-modules/TextAnalysisModule.js
index 69b663d..d34ee14 100644
--- a/src/DRS/exercise-modules/TextAnalysisModule.js
+++ b/src/DRS/exercise-modules/TextAnalysisModule.js
@@ -1,13 +1,14 @@
 /**
  * TextAnalysisModule - Open-text comprehension with AI validation
  * Presents text passages with open questions, validates free-text responses using AI
+ * Implements DRSExerciseInterface for strict contract enforcement
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class TextAnalysisModule extends ExerciseModuleInterface {
+class TextAnalysisModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('TextAnalysisModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -661,6 +662,174 @@ Return ONLY a JSON array:
 
         setTimeout(() => errorDiv.remove(), 5000);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    /**
+     * Initialize the exercise module
+     * @param {Object} config - Exercise configuration
+     * @param {Object} content - Exercise content data
+     * @returns {Promise<void>}
+     */
+    async init(config = {}, content = {}) {
+        console.log('📖 Initializing TextAnalysisModule...');
+
+        // Merge provided config with defaults
+        this.config = {
+            ...this.config,
+            ...config
+        };
+
+        // Store content
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+
+        console.log('✅ TextAnalysisModule initialized');
+    }
+
+    /**
+     * Render the exercise UI
+     * @param {HTMLElement} container - Container element to render into
+     * @returns {Promise<void>}
+     */
+    async render(container) {
+        if (!this.initialized) {
+            throw new Error('TextAnalysisModule must be initialized before rendering');
+        }
+
+        // Use existing present() logic
+        await this.present(container, this.currentExerciseData);
+    }
+
+    /**
+     * Clean up and destroy the exercise
+     * @returns {Promise<void>}
+     */
+    async destroy() {
+        console.log('🧹 Destroying TextAnalysisModule...');
+
+        // Use existing cleanup
+        this.cleanup();
+
+        console.log('✅ TextAnalysisModule destroyed');
+    }
+
+    /**
+     * Get exercise results and statistics
+     * @returns {Object} - Results data
+     */
+    getResults() {
+        const totalQuestions = this.questions ? this.questions.length : 0;
+        const answeredQuestions = this.userResponses.length;
+        const averageScore = this.progress.averageScore;
+        const timeSpent = this.startTime ? Date.now() - this.startTime : 0;
+
+        return {
+            score: Math.round(averageScore * 100),
+            attempts: answeredQuestions,
+            timeSpent,
+            completed: answeredQuestions >= totalQuestions,
+            details: {
+                totalQuestions,
+                answeredQuestions,
+                averageScore,
+                qualityMetrics: this.progress.qualityMetrics,
+                responses: this.userResponses
+            }
+        };
+    }
+
+    /**
+     * Handle user input during exercise
+     * @param {Event} event - User input event
+     * @param {*} data - Input data
+     * @returns {void}
+     */
+    handleUserInput(event, data) {
+        // Delegate to existing handlers
+        if (event && event.type) {
+            switch (event.type) {
+                case 'input':
+                    this._handleInputChange(event);
+                    break;
+                case 'click':
+                    if (event.target.id === 'submitButton') {
+                        this._handleSubmit(event);
+                    }
+                    break;
+            }
+        }
+    }
+
+    /**
+     * Mark exercise as completed and save progress
+     * @param {Object} results - Exercise results
+     * @returns {Promise<void>}
+     */
+    async markCompleted(results) {
+        console.log('💾 Marking TextAnalysisModule as completed...');
+
+        const { score, details } = results || this.getResults();
+
+        // Save completion metadata
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'text-analysis',
+                subtype: 'completion',
+                content: {
+                    text: this.currentText,
+                    questions: this.questions
+                },
+                userResponse: this.userResponses,
+                validation: {
+                    score,
+                    averageScore: details.averageScore,
+                    qualityMetrics: details.qualityMetrics
+                },
+                context: {
+                    moduleType: 'text-analysis',
+                    totalQuestions: details.totalQuestions,
+                    answeredQuestions: details.answeredQuestions
+                }
+            });
+        }
+
+        console.log('✅ TextAnalysisModule completion saved');
+    }
+
+    /**
+     * Get exercise type identifier
+     * @returns {string} - Exercise type
+     */
+    getExerciseType() {
+        return 'text-analysis';
+    }
+
+    /**
+     * Get exercise configuration
+     * @returns {Object} - Configuration object
+     */
+    getExerciseConfig() {
+        const questionCount = this.questions ? this.questions.length : 2;
+        const estimatedTimePerQuestion = 3; // 3 minutes per question
+
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: questionCount * estimatedTimePerQuestion,
+            prerequisites: [], // Text analysis requires no specific prerequisites
+            metadata: {
+                ...this.config,
+                questionCount,
+                textLength: this.currentText ? this.currentText.length : 0,
+                requiresAI: true,
+                model: this.config.model
+            }
+        };
+    }
 }
 
 export default TextAnalysisModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/TextModule.js b/src/DRS/exercise-modules/TextModule.js
index 398d4d9..d3aa6da 100644
--- a/src/DRS/exercise-modules/TextModule.js
+++ b/src/DRS/exercise-modules/TextModule.js
@@ -3,11 +3,11 @@
  * Handles text passages with comprehension questions and contextual understanding
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class TextModule extends ExerciseModuleInterface {
+class TextModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('TextModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -1505,6 +1505,71 @@ Format: [answer]yes/no [explanation]your comprehensive educational feedback here
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('TextModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'text',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'text' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'text';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default TextModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/TranslationModule.js b/src/DRS/exercise-modules/TranslationModule.js
index 2ca72e3..a9539ab 100644
--- a/src/DRS/exercise-modules/TranslationModule.js
+++ b/src/DRS/exercise-modules/TranslationModule.js
@@ -1,13 +1,14 @@
 /**
  * TranslationModule - AI-validated translation exercises
  * Presents translation challenges with intelligent AI feedback on accuracy and fluency
+ * Implements DRSExerciseInterface for strict contract enforcement
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class TranslationModule extends ExerciseModuleInterface {
+class TranslationModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('TranslationModule');
 
         // Validate dependencies
         if (!orchestrator || !llmValidator || !prerequisiteEngine || !contextMemory) {
@@ -766,6 +767,79 @@ Return ONLY valid JSON:
 
         setTimeout(() => errorDiv.remove(), 5000);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('TranslationModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup();
+    }
+
+    getResults() {
+        const totalPhrases = this.currentPhrases ? this.currentPhrases.length : 0;
+        const translatedPhrases = this.userTranslations ? this.userTranslations.length : 0;
+        const score = this.progress ? Math.round(this.progress.averageAccuracy * 100) : 0;
+
+        return {
+            score,
+            attempts: translatedPhrases,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: translatedPhrases >= totalPhrases,
+            details: {
+                totalPhrases,
+                translatedPhrases,
+                averageAccuracy: this.progress?.averageAccuracy || 0,
+                translations: this.userTranslations || []
+            }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event && event.type === 'input') this._handleInputChange?.(event);
+        if (event && event.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'translation',
+                subtype: 'completion',
+                content: { phrases: this.currentPhrases },
+                userResponse: this.userTranslations,
+                validation: { score, averageAccuracy: details.averageAccuracy },
+                context: { moduleType: 'translation', totalPhrases: details.totalPhrases }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'translation';
+    }
+
+    getExerciseConfig() {
+        const phraseCount = this.currentPhrases ? this.currentPhrases.length : this.config?.phrasesPerExercise || 3;
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: phraseCount * 2, // 2 min per phrase
+            prerequisites: [],
+            metadata: { ...this.config, phraseCount, requiresAI: true }
+        };
+    }
 }
 
 export default TranslationModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/VocabularyModule.js b/src/DRS/exercise-modules/VocabularyModule.js
index a3c4b60..7b807bd 100644
--- a/src/DRS/exercise-modules/VocabularyModule.js
+++ b/src/DRS/exercise-modules/VocabularyModule.js
@@ -1,13 +1,13 @@
 /**
  * VocabularyModule - Groups of 5 vocabulary exercise implementation
- * First exercise module following the ExerciseModuleInterface
+ * Implements DRSExerciseInterface for strict contract enforcement
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class VocabularyModule extends ExerciseModuleInterface {
+class VocabularyModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('VocabularyModule');
 
         // Validate dependencies (llmValidator can be null since we use local validation)
         if (!orchestrator || !prerequisiteEngine || !contextMemory) {
@@ -44,14 +44,84 @@ class VocabularyModule extends ExerciseModuleInterface {
         this._handleDifficultySelection = this._handleDifficultySelection.bind(this);
     }
 
-    async init() {
+    /**
+     * Initialize the exercise module
+     * @param {Object} config - Exercise configuration
+     * @param {Object} content - Exercise content data
+     * @returns {Promise<void>}
+     */
+    async init(config = {}, content = {}) {
         if (this.initialized) return;
 
         console.log('📚 Initializing VocabularyModule...');
+
+        // Merge provided config with defaults
+        this.config = {
+            ...this.config,
+            ...config
+        };
+
+        // Store content for later use
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+
         this.initialized = true;
         console.log('✅ VocabularyModule initialized');
     }
 
+    /**
+     * Render the exercise UI
+     * @param {HTMLElement} container - Container element to render into
+     * @returns {Promise<void>}
+     */
+    async render(container) {
+        if (!this.initialized) {
+            throw new Error('VocabularyModule must be initialized before rendering');
+        }
+
+        // Use existing present() logic
+        await this.present(container, this.currentExerciseData);
+    }
+
+    /**
+     * Clean up and destroy the exercise
+     * @returns {Promise<void>}
+     */
+    async destroy() {
+        console.log('🧹 Destroying VocabularyModule...');
+
+        // Remove event listeners
+        if (this.container) {
+            const input = this.container.querySelector('.vocabulary-input');
+            const submitBtn = this.container.querySelector('.btn-submit');
+            const revealBtn = this.container.querySelector('.btn-reveal');
+            const nextBtn = this.container.querySelector('.btn-next');
+            const difficultyButtons = this.container.querySelectorAll('.difficulty-btn');
+
+            if (input) input.removeEventListener('input', this._handleUserInput);
+            if (submitBtn) submitBtn.removeEventListener('click', this._handleUserInput);
+            if (revealBtn) revealBtn.removeEventListener('click', this._handleRevealAnswer);
+            if (nextBtn) nextBtn.removeEventListener('click', this._handleNextWord);
+            difficultyButtons.forEach(btn => {
+                btn.removeEventListener('click', this._handleDifficultySelection);
+            });
+
+            // Clear container
+            this.container.innerHTML = '';
+            this.container = null;
+        }
+
+        // Reset state
+        this.currentVocabularyGroup = [];
+        this.currentWordIndex = 0;
+        this.groupResults = [];
+        this.isRevealed = false;
+        this.currentExerciseData = null;
+        this.initialized = false;
+
+        console.log('✅ VocabularyModule destroyed');
+    }
+
     /**
      * Check if module can run with current prerequisites
      * @param {Array} prerequisites - List of learned vocabulary/concepts
@@ -1196,6 +1266,144 @@ class VocabularyModule extends ExerciseModuleInterface {
 
         document.head.appendChild(styles);
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    /**
+     * Get exercise results and statistics
+     * @returns {Object} - Results data
+     */
+    getResults() {
+        const correctWords = this.groupResults.filter(result => result.correct).length;
+        const totalWords = this.groupResults.length;
+        const score = totalWords > 0 ? Math.round((correctWords / totalWords) * 100) : 0;
+        const timeSpent = this.startTime ? Date.now() - this.startTime : 0;
+
+        return {
+            score,
+            attempts: totalWords,
+            timeSpent,
+            completed: this.currentWordIndex >= this.currentVocabularyGroup.length,
+            details: {
+                correctWords,
+                totalWords,
+                currentGroupIndex: this.currentGroupIndex,
+                totalGroups: this.allVocabularyGroups ? this.allVocabularyGroups.length : 1,
+                groupResults: this.groupResults,
+                masteryPercentage: score
+            }
+        };
+    }
+
+    /**
+     * Handle user input during exercise
+     * @param {Event} event - User input event
+     * @param {*} data - Input data
+     * @returns {void}
+     */
+    handleUserInput(event, data) {
+        // This method delegates to existing handlers
+        // Already implemented through _handleUserInput, _handleDifficultySelection, etc.
+        if (event && event.type) {
+            switch (event.type) {
+                case 'input':
+                case 'change':
+                    this._handleUserInput(event);
+                    break;
+                case 'click':
+                    if (event.target.classList.contains('difficulty-btn')) {
+                        this._handleDifficultySelection(event);
+                    } else if (event.target.classList.contains('btn-next')) {
+                        this._handleNextWord(event);
+                    } else if (event.target.classList.contains('btn-reveal')) {
+                        this._handleRevealAnswer(event);
+                    }
+                    break;
+            }
+        }
+    }
+
+    /**
+     * Mark exercise as completed and save progress
+     * @param {Object} results - Exercise results
+     * @returns {Promise<void>}
+     */
+    async markCompleted(results) {
+        console.log('💾 Marking VocabularyModule as completed...');
+
+        // Mark all words in current group as mastered if score is high enough
+        const { score, details } = results || this.getResults();
+
+        if (score >= this.config.masteryThreshold) {
+            // Mark all words in group as mastered
+            for (const word of this.currentVocabularyGroup) {
+                if (this.prerequisiteEngine && this.prerequisiteEngine.isInitialized) {
+                    await this.prerequisiteEngine.markWordMastered(word.word, {
+                        score,
+                        timestamp: new Date().toISOString(),
+                        moduleType: 'vocabulary',
+                        attempts: details.totalWords
+                    });
+                }
+            }
+            console.log(`✅ Marked ${this.currentVocabularyGroup.length} words as mastered`);
+        } else {
+            console.log(`⚠️ Score ${score}% below mastery threshold ${this.config.masteryThreshold}%`);
+        }
+
+        // Save completion metadata
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'vocabulary',
+                subtype: 'completion',
+                content: {
+                    vocabulary: this.currentVocabularyGroup
+                },
+                validation: results,
+                context: {
+                    moduleType: 'vocabulary',
+                    groupIndex: this.currentGroupIndex,
+                    totalGroups: this.allVocabularyGroups ? this.allVocabularyGroups.length : 1
+                }
+            });
+        }
+
+        console.log('✅ VocabularyModule completion saved');
+    }
+
+    /**
+     * Get exercise type identifier
+     * @returns {string} - Exercise type
+     */
+    getExerciseType() {
+        return 'vocabulary';
+    }
+
+    /**
+     * Get exercise configuration
+     * @returns {Object} - Configuration object
+     */
+    getExerciseConfig() {
+        const wordCount = this.currentVocabularyGroup ? this.currentVocabularyGroup.length : 0;
+        const estimatedTimePerWord = 0.5; // 30 seconds per word
+
+        return {
+            type: this.getExerciseType(),
+            difficulty: wordCount <= 3 ? 'easy' : (wordCount <= 7 ? 'medium' : 'hard'),
+            estimatedTime: Math.ceil(wordCount * estimatedTimePerWord), // in minutes
+            prerequisites: [], // Vocabulary has no prerequisites
+            metadata: {
+                ...this.config,
+                groupSize: this.config.groupSize,
+                masteryThreshold: this.config.masteryThreshold,
+                currentGroupIndex: this.currentGroupIndex,
+                totalGroups: this.allVocabularyGroups ? this.allVocabularyGroups.length : 1,
+                wordCount
+            }
+        };
+    }
 }
 
 export default VocabularyModule;
\ No newline at end of file
diff --git a/src/DRS/exercise-modules/WordDiscoveryModule.js b/src/DRS/exercise-modules/WordDiscoveryModule.js
index 4761993..8e0fd52 100644
--- a/src/DRS/exercise-modules/WordDiscoveryModule.js
+++ b/src/DRS/exercise-modules/WordDiscoveryModule.js
@@ -3,11 +3,11 @@
  * Shows word, pronunciation, meaning, and example before flashcard practice
  */
 
-import ExerciseModuleInterface from '../interfaces/ExerciseModuleInterface.js';
+import DRSExerciseInterface from '../interfaces/DRSExerciseInterface.js';
 
-class WordDiscoveryModule extends ExerciseModuleInterface {
+class WordDiscoveryModule extends DRSExerciseInterface {
     constructor(orchestrator, llmValidator, prerequisiteEngine, contextMemory) {
-        super();
+        super('WordDiscoveryModule');
         this.orchestrator = orchestrator;
         this.llmValidator = llmValidator;
         this.prerequisiteEngine = prerequisiteEngine;
@@ -362,6 +362,71 @@ class WordDiscoveryModule extends ExerciseModuleInterface {
             prerequisites: []
         };
     }
+
+    // ========================================
+    // DRSExerciseInterface REQUIRED METHODS
+    // ========================================
+
+    async init(config = {}, content = {}) {
+        this.config = { ...this.config, ...config };
+        this.currentExerciseData = content;
+        this.startTime = Date.now();
+        this.initialized = true;
+    }
+
+    async render(container) {
+        if (!this.initialized) throw new Error('WordDiscoveryModule must be initialized before rendering');
+        await this.present(container, this.currentExerciseData);
+    }
+
+    async destroy() {
+        this.cleanup?.();
+        this.container = null;
+        this.initialized = false;
+    }
+
+    getResults() {
+        return {
+            score: this.progress?.averageScore ? Math.round(this.progress.averageScore * 100) : 0,
+            attempts: this.userResponses?.length || 0,
+            timeSpent: this.startTime ? Date.now() - this.startTime : 0,
+            completed: true,
+            details: { progress: this.progress, responses: this.userResponses }
+        };
+    }
+
+    handleUserInput(event, data) {
+        if (event?.type === 'input') this._handleInputChange?.(event);
+        if (event?.type === 'click' && event.target.id === 'submitButton') this._handleSubmit?.(event);
+    }
+
+    async markCompleted(results) {
+        const { score, details } = results || this.getResults();
+        if (this.contextMemory) {
+            this.contextMemory.recordInteraction({
+                type: 'word-discovery',
+                subtype: 'completion',
+                content: this.currentExerciseData,
+                validation: { score },
+                context: { moduleType: 'word-discovery' }
+            });
+        }
+    }
+
+    getExerciseType() {
+        return 'word-discovery';
+    }
+
+    getExerciseConfig() {
+        return {
+            type: this.getExerciseType(),
+            difficulty: this.currentExerciseData?.difficulty || 'medium',
+            estimatedTime: 5,
+            prerequisites: [],
+            metadata: { ...this.config, requiresAI: false }
+        };
+    }
+
 }
 
 export default WordDiscoveryModule;
\ No newline at end of file
diff --git a/src/DRS/interfaces/DRSExerciseInterface.js b/src/DRS/interfaces/DRSExerciseInterface.js
new file mode 100644
index 0000000..324b47a
--- /dev/null
+++ b/src/DRS/interfaces/DRSExerciseInterface.js
@@ -0,0 +1,181 @@
+/**
+ * DRSExerciseInterface - STRICT interface for all DRS exercise modules
+ * Like a .h header in C++ - ALL exercise modules MUST implement these methods
+ *
+ * ANY module wanting to work with DRS/SmartGuide MUST implement this interface
+ */
+
+import StrictInterface from './StrictInterface.js';
+
+class DRSExerciseInterface extends StrictInterface {
+    constructor(implementationName) {
+        super(implementationName);
+    }
+
+    /**
+     * Define required methods that ALL DRS exercise modules MUST implement
+     * @override
+     */
+    _getAbstractMethods() {
+        return [
+            // Lifecycle
+            'init',
+            'render',
+            'destroy',
+
+            // Exercise logic
+            'validate',
+            'getResults',
+            'handleUserInput',
+
+            // Progress tracking
+            'markCompleted',
+            'getProgress',
+
+            // Metadata
+            'getExerciseType',
+            'getExerciseConfig'
+        ];
+    }
+
+    // ========================================
+    // LIFECYCLE METHODS (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Initialize the exercise module
+     * @param {Object} config - Exercise configuration
+     * @param {Object} content - Exercise content data
+     * @returns {Promise<void>}
+     */
+    async init(config, content) {
+        this._throwImplementationError('init');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Render the exercise UI
+     * @param {HTMLElement} container - Container element to render into
+     * @returns {Promise<void>}
+     */
+    async render(container) {
+        this._throwImplementationError('render');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Clean up and destroy the exercise
+     * @returns {Promise<void>}
+     */
+    async destroy() {
+        this._throwImplementationError('destroy');
+    }
+
+    // ========================================
+    // EXERCISE LOGIC (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Validate user's answer
+     * @param {*} userAnswer - User's answer (format depends on exercise type)
+     * @returns {Promise<Object>} - Validation result
+     *
+     * MUST return format:
+     * {
+     *   isCorrect: boolean,
+     *   score: number,           // 0-100
+     *   feedback: string,
+     *   explanation: string,
+     *   metadata: Object         // Exercise-specific data
+     * }
+     */
+    async validate(userAnswer) {
+        this._throwImplementationError('validate');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Get exercise results and statistics
+     * @returns {Object} - Results data
+     *
+     * MUST return format:
+     * {
+     *   score: number,           // 0-100
+     *   attempts: number,
+     *   timeSpent: number,       // milliseconds
+     *   completed: boolean,
+     *   details: Object          // Exercise-specific details
+     * }
+     */
+    getResults() {
+        this._throwImplementationError('getResults');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Handle user input during exercise
+     * @param {Event} event - User input event
+     * @param {*} data - Input data
+     * @returns {void}
+     */
+    handleUserInput(event, data) {
+        this._throwImplementationError('handleUserInput');
+    }
+
+    // ========================================
+    // PROGRESS TRACKING (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark exercise as completed and save progress
+     * @param {Object} results - Exercise results
+     * @returns {Promise<void>}
+     */
+    async markCompleted(results) {
+        this._throwImplementationError('markCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Get current exercise progress
+     * @returns {Object} - Progress data
+     *
+     * MUST return format:
+     * {
+     *   percentage: number,      // 0-100
+     *   currentStep: number,
+     *   totalSteps: number,
+     *   itemsCompleted: number,
+     *   itemsTotal: number
+     * }
+     */
+    getProgress() {
+        this._throwImplementationError('getProgress');
+    }
+
+    // ========================================
+    // METADATA (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Get exercise type identifier
+     * @returns {string} - Exercise type (e.g., 'vocabulary', 'text-analysis', 'grammar')
+     */
+    getExerciseType() {
+        this._throwImplementationError('getExerciseType');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Get exercise configuration
+     * @returns {Object} - Configuration object
+     *
+     * MUST return format:
+     * {
+     *   type: string,            // Exercise type
+     *   difficulty: string,      // 'easy', 'medium', 'hard'
+     *   estimatedTime: number,   // minutes
+     *   prerequisites: Array,    // Required prerequisites
+     *   metadata: Object         // Exercise-specific config
+     * }
+     */
+    getExerciseConfig() {
+        this._throwImplementationError('getExerciseConfig');
+    }
+}
+
+export default DRSExerciseInterface;
diff --git a/src/DRS/interfaces/ProgressSystemInterface.js b/src/DRS/interfaces/ProgressSystemInterface.js
new file mode 100644
index 0000000..6fc8891
--- /dev/null
+++ b/src/DRS/interfaces/ProgressSystemInterface.js
@@ -0,0 +1,232 @@
+/**
+ * ProgressSystemInterface - STRICT interface for all DRS progress systems
+ * Like a .h header in C++ - ALL progress systems MUST implement these methods
+ *
+ * ANY system wanting to work with DRS/SmartGuide MUST implement this interface
+ */
+
+import StrictInterface from './StrictInterface.js';
+
+class ProgressSystemInterface extends StrictInterface {
+    constructor(implementationName) {
+        super(implementationName);
+    }
+
+    /**
+     * Define required methods that ALL progress systems MUST implement
+     * @override
+     */
+    _getAbstractMethods() {
+        return [
+            // Vocabulary tracking
+            'markWordDiscovered',
+            'markWordMastered',
+            'isWordDiscovered',
+            'isWordMastered',
+
+            // Content tracking
+            'markPhraseCompleted',
+            'markDialogCompleted',
+            'markTextCompleted',
+            'markAudioCompleted',
+            'markImageCompleted',
+            'markGrammarCompleted',
+
+            // Prerequisites
+            'canComplete',
+
+            // Progress calculation
+            'getProgress',
+
+            // Persistence
+            'saveProgress',
+            'loadProgress',
+
+            // Utility
+            'reset'
+        ];
+    }
+
+    // ========================================
+    // VOCABULARY METHODS (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark a word as discovered (passive exposure)
+     * @param {string} word - Word to mark as discovered
+     * @param {Object} metadata - Optional metadata (timestamp, context, etc.)
+     * @returns {Promise<void>}
+     */
+    async markWordDiscovered(word, metadata = {}) {
+        this._throwImplementationError('markWordDiscovered');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark a word as mastered (active practice)
+     * @param {string} word - Word to mark as mastered
+     * @param {Object} metadata - Optional metadata (score, attempts, etc.)
+     * @returns {Promise<void>}
+     */
+    async markWordMastered(word, metadata = {}) {
+        this._throwImplementationError('markWordMastered');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Check if word is discovered
+     * @param {string} word - Word to check
+     * @returns {boolean}
+     */
+    isWordDiscovered(word) {
+        this._throwImplementationError('isWordDiscovered');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Check if word is mastered
+     * @param {string} word - Word to check
+     * @returns {boolean}
+     */
+    isWordMastered(word) {
+        this._throwImplementationError('isWordMastered');
+    }
+
+    // ========================================
+    // CONTENT TRACKING METHODS (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark phrase as completed
+     * @param {string} phraseId - Phrase identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markPhraseCompleted(phraseId, metadata = {}) {
+        this._throwImplementationError('markPhraseCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark dialog as completed
+     * @param {string} dialogId - Dialog identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markDialogCompleted(dialogId, metadata = {}) {
+        this._throwImplementationError('markDialogCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark text/lesson as completed
+     * @param {string} textId - Text identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markTextCompleted(textId, metadata = {}) {
+        this._throwImplementationError('markTextCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark audio as completed
+     * @param {string} audioId - Audio identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markAudioCompleted(audioId, metadata = {}) {
+        this._throwImplementationError('markAudioCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark image as completed
+     * @param {string} imageId - Image identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markImageCompleted(imageId, metadata = {}) {
+        this._throwImplementationError('markImageCompleted');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Mark grammar concept as completed
+     * @param {string} grammarId - Grammar identifier
+     * @param {Object} metadata - Optional metadata
+     * @returns {Promise<void>}
+     */
+    async markGrammarCompleted(grammarId, metadata = {}) {
+        this._throwImplementationError('markGrammarCompleted');
+    }
+
+    // ========================================
+    // PREREQUISITE CHECKING (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Check if an item can be completed (prerequisites met)
+     * @param {string} itemType - Type of item (vocabulary-discovery, phrase, dialog, etc.)
+     * @param {string} itemId - Item identifier
+     * @param {Object} context - Additional context (chapter content, etc.)
+     * @returns {Object} - { canComplete: boolean, reason: string, missingPrereqs: Array }
+     */
+    canComplete(itemType, itemId, context = {}) {
+        this._throwImplementationError('canComplete');
+    }
+
+    // ========================================
+    // PROGRESS CALCULATION (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Get current progress for a chapter
+     * @param {string} chapterId - Chapter identifier
+     * @returns {Object} - Progress data with percentage, breakdown, etc.
+     *
+     * MUST return format:
+     * {
+     *   percentage: number,           // 0-100
+     *   completedWeight: number,      // Total weight completed
+     *   totalWeight: number,          // Total possible weight
+     *   breakdown: Object,            // By item type
+     *   completedBreakdown: Object    // Completed items by type
+     * }
+     */
+    getProgress(chapterId) {
+        this._throwImplementationError('getProgress');
+    }
+
+    // ========================================
+    // PERSISTENCE (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Save progress to persistent storage
+     * @param {string} bookId - Book identifier
+     * @param {string} chapterId - Chapter identifier
+     * @returns {Promise<void>}
+     */
+    async saveProgress(bookId, chapterId) {
+        this._throwImplementationError('saveProgress');
+    }
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Load progress from persistent storage
+     * @param {string} bookId - Book identifier
+     * @param {string} chapterId - Chapter identifier
+     * @returns {Promise<Object>} - Loaded progress data
+     */
+    async loadProgress(bookId, chapterId) {
+        this._throwImplementationError('loadProgress');
+    }
+
+    // ========================================
+    // UTILITY (REQUIRED)
+    // ========================================
+
+    /**
+     * ⚠️ MUST IMPLEMENT - Reset all progress for a chapter
+     * @param {string} bookId - Book identifier
+     * @param {string} chapterId - Chapter identifier
+     * @returns {Promise<void>}
+     */
+    async reset(bookId, chapterId) {
+        this._throwImplementationError('reset');
+    }
+}
+
+export default ProgressSystemInterface;
diff --git a/src/DRS/services/ImplementationValidator.js b/src/DRS/services/ImplementationValidator.js
index f8977b3..8ec8794 100644
--- a/src/DRS/services/ImplementationValidator.js
+++ b/src/DRS/services/ImplementationValidator.js
@@ -16,13 +16,20 @@ import {
 
 class ImplementationValidator {
     static async validateAll() {
-        console.log('%c🔍 VALIDATING PROGRESS ITEM IMPLEMENTATIONS...',
+        console.log('%c🔍 VALIDATING DRS IMPLEMENTATIONS...',
             'background: #3b82f6; color: white; font-size: 16px; padding: 8px; font-weight: bold;'
         );
 
         const errors = [];
         const validations = [];
 
+        // ========================================
+        // 1. VALIDATE PROGRESS ITEMS
+        // ========================================
+        console.log('%c📦 PART 1: Validating Progress Items...',
+            'background: #6366f1; color: white; font-size: 14px; padding: 6px; font-weight: bold;'
+        );
+
         // Test VocabularyDiscoveryItem
         validations.push(
             this._testItem('VocabularyDiscoveryItem', () =>
@@ -79,15 +86,108 @@ class ImplementationValidator {
             )
         );
 
-        // Wait for all validations
-        const results = await Promise.allSettled(validations);
+        // Wait for all item validations
+        const itemResults = await Promise.allSettled(validations);
 
-        results.forEach((result, index) => {
+        itemResults.forEach((result, index) => {
             if (result.status === 'rejected') {
                 errors.push(result.reason);
             }
         });
 
+        // ========================================
+        // 2. VALIDATE PROGRESS SYSTEMS
+        // ========================================
+        console.log('%c🔧 PART 2: Validating Progress Systems...',
+            'background: #6366f1; color: white; font-size: 14px; padding: 6px; font-weight: bold;'
+        );
+
+        const systemValidations = [];
+
+        // Test ProgressTracker (if it implements ProgressSystemInterface)
+        systemValidations.push(
+            this._testProgressSystem('ProgressTracker', async () => {
+                const { default: ProgressTracker } = await import('./ProgressTracker.js');
+                return ProgressTracker;
+            })
+        );
+
+        // Test PrerequisiteEngine (if it implements ProgressSystemInterface)
+        systemValidations.push(
+            this._testProgressSystem('PrerequisiteEngine', async () => {
+                const { default: PrerequisiteEngine } = await import('./PrerequisiteEngine.js');
+                return PrerequisiteEngine;
+            })
+        );
+
+        const systemResults = await Promise.allSettled(systemValidations);
+
+        systemResults.forEach((result, index) => {
+            if (result.status === 'rejected') {
+                errors.push(result.reason);
+            }
+        });
+
+        // ========================================
+        // 3. VALIDATE DRS EXERCISE MODULES
+        // ========================================
+        console.log('%c🎮 PART 3: Validating DRS Exercise Modules...',
+            'background: #6366f1; color: white; font-size: 14px; padding: 6px; font-weight: bold;'
+        );
+
+        const exerciseValidations = [];
+
+        // Test VocabularyModule
+        exerciseValidations.push(
+            this._testExerciseModule('VocabularyModule', async () => {
+                const { default: VocabularyModule } = await import('../exercise-modules/VocabularyModule.js');
+                return VocabularyModule;
+            })
+        );
+
+        // Test TextAnalysisModule
+        exerciseValidations.push(
+            this._testExerciseModule('TextAnalysisModule', async () => {
+                const { default: TextAnalysisModule } = await import('../exercise-modules/TextAnalysisModule.js');
+                return TextAnalysisModule;
+            })
+        );
+
+        // Test GrammarAnalysisModule
+        exerciseValidations.push(
+            this._testExerciseModule('GrammarAnalysisModule', async () => {
+                const { default: GrammarAnalysisModule } = await import('../exercise-modules/GrammarAnalysisModule.js');
+                return GrammarAnalysisModule;
+            })
+        );
+
+        // Test TranslationModule
+        exerciseValidations.push(
+            this._testExerciseModule('TranslationModule', async () => {
+                const { default: TranslationModule } = await import('../exercise-modules/TranslationModule.js');
+                return TranslationModule;
+            })
+        );
+
+        // Test OpenResponseModule
+        exerciseValidations.push(
+            this._testExerciseModule('OpenResponseModule', async () => {
+                const { default: OpenResponseModule } = await import('../exercise-modules/OpenResponseModule.js');
+                return OpenResponseModule;
+            })
+        );
+
+        const exerciseResults = await Promise.allSettled(exerciseValidations);
+
+        exerciseResults.forEach((result, index) => {
+            if (result.status === 'rejected') {
+                errors.push(result.reason);
+            }
+        });
+
+        // ========================================
+        // FINAL RESULT
+        // ========================================
         if (errors.length > 0) {
             console.error('%c❌ VALIDATION FAILED',
                 'background: red; color: white; font-size: 20px; padding: 10px; font-weight: bold;'
@@ -96,7 +196,7 @@ class ImplementationValidator {
             return false;
         }
 
-        console.log('%c✅ ALL IMPLEMENTATIONS VALID',
+        console.log('%c✅ ALL DRS IMPLEMENTATIONS VALID',
             'background: #10b981; color: white; font-size: 16px; padding: 8px; font-weight: bold;'
         );
         return true;
@@ -129,6 +229,103 @@ class ImplementationValidator {
             throw error;
         }
     }
+
+    static async _testProgressSystem(systemName, loadFn) {
+        try {
+            const SystemClass = await loadFn();
+
+            // Required methods from ProgressSystemInterface
+            const requiredMethods = [
+                // Vocabulary
+                'markWordDiscovered',
+                'markWordMastered',
+                'isWordDiscovered',
+                'isWordMastered',
+                // Content
+                'markPhraseCompleted',
+                'markDialogCompleted',
+                'markTextCompleted',
+                'markAudioCompleted',
+                'markImageCompleted',
+                'markGrammarCompleted',
+                // Prerequisites
+                'canComplete',
+                // Progress
+                'getProgress',
+                // Persistence
+                'saveProgress',
+                'loadProgress',
+                // Utility
+                'reset'
+            ];
+
+            const missingMethods = [];
+
+            // Check prototype for methods
+            requiredMethods.forEach(method => {
+                if (typeof SystemClass.prototype[method] !== 'function') {
+                    missingMethods.push(method);
+                }
+            });
+
+            if (missingMethods.length > 0) {
+                throw new Error(
+                    `${systemName} is missing ProgressSystemInterface methods: ${missingMethods.join(', ')}`
+                );
+            }
+
+            console.log(`✅ ${systemName} - OK`);
+            return true;
+        } catch (error) {
+            console.error(`❌ ${systemName} - FAILED:`, error.message);
+            throw error;
+        }
+    }
+
+    static async _testExerciseModule(moduleName, loadFn) {
+        try {
+            const ModuleClass = await loadFn();
+
+            // Required methods from DRSExerciseInterface
+            const requiredMethods = [
+                // Lifecycle
+                'init',
+                'render',
+                'destroy',
+                // Exercise logic
+                'validate',
+                'getResults',
+                'handleUserInput',
+                // Progress tracking
+                'markCompleted',
+                'getProgress',
+                // Metadata
+                'getExerciseType',
+                'getExerciseConfig'
+            ];
+
+            const missingMethods = [];
+
+            // Check prototype for methods
+            requiredMethods.forEach(method => {
+                if (typeof ModuleClass.prototype[method] !== 'function') {
+                    missingMethods.push(method);
+                }
+            });
+
+            if (missingMethods.length > 0) {
+                throw new Error(
+                    `${moduleName} is missing DRSExerciseInterface methods: ${missingMethods.join(', ')}`
+                );
+            }
+
+            console.log(`✅ ${moduleName} - OK`);
+            return true;
+        } catch (error) {
+            console.error(`❌ ${moduleName} - FAILED:`, error.message);
+            throw error;
+        }
+    }
 }
 
 export default ImplementationValidator;