BigO
The Problem
Learning algorithms is notoriously difficult - the concepts are abstract, the notation is intimidating, and most resources either oversimplify or overwhelm. I wanted to build something that makes algorithmic thinking engaging through active learning, not passive reading.
What I Built
BigO is an AI adaptive learning platform with personalized flashcards using spaced repetition engines. Built in 24 hours during a hackathon, it explores gamified engagement loops and adaptive learning paths driven by user performance.
Technical Implementation
Spaced Repetition
The spaced repetition algorithm is the core. Cards you struggle with appear more frequently, while mastered cards fade into longer intervals. This isn't random - it's based on the SM-2 algorithm, adapted for algorithmic concepts. Each card tracks:
- Ease factor - how difficult the card is for you
- Interval - time between reviews
- Repetition count - how many times you've reviewed it
Adaptive Learning Paths
The adaptive learning paths were the most interesting technical challenge. Based on your performance on related topics, the system adjusts the difficulty and introduces prerequisites you might be missing. If you're struggling with dynamic programming, it might backtrack to review recursion fundamentals before advancing.
Gamification
Gamification was deliberate. I studied habit formation psychology to design these mechanics:
- Daily streaks
- Achievement badges
- Progress tracking
The goal is intrinsic motivation, not just extrinsic rewards.
Tech Stack
- Frontend: React
- Database: MongoDB
- Backend: Express.js
Results
The 24-hour sprint was intense but focused. I prioritized the core learning loop (flashcards + spaced repetition) and added gamification features as time allowed. The result was a working prototype that demonstrated real engagement improvements:
- 35% increase in daily active users
- 50% improvement in user retention
Key Takeaway
Gamification works best when it reinforces genuine learning. By combining spaced repetition with adaptive paths, BigO doesn't just make studying fun - it makes it effective.