Pluto — AI Study Partner

What is Pluto?

I'm a high schooler from Georgia. Tutoring costs $25–$100/hour. 70% of students can't afford it. Premium study apps charge subscription fees. AI tools hallucinate fake sources. The system is broken — and it's broken on purpose. Rich kids get better test prep. Poor kids don't. That gap shouldn't exist.

Pluto is a Chrome extension that lives where you study. It costs $0. It will always cost $0. It automates the busywork, powers real AP practice tests anchored to actual College Board standards, and grows smarter every time another student uses it. This is what equitable education looks like.

What I Built

Dashboard: Central hub showing all 8 study modes, real-time shared brain stats, activity feed
Practice Tests: Full mock exams (60 for AP Bio, 55 for AP USH), authentic stimuli, instant grading with topic breakdown, AI verdict
Flashcard Study: AI generation, flip/write mode, shared brain integration
Spaced Repetition (Learn): Adaptive scheduling, optimal retention timing
Multiplayer Match Game: Drag-and-drop, real-time leaderboard, 60-second rounds
Kai Voice Tutor: Web Speech API, speak questions, active recall
PDF/YouTube Importer: Extract text, auto-generate cards
Live Multiplayer Race: Real-time Firestore leaderboard
Canvas New Quizzes Automation: Auto-detect and answer Canvas quizzes seamlessly

Standards RAG: All 38 AP courses (448 MB) embedded in vector database. Every question shows real CED codes with source citations. Click any standard → AI explanation → open chat for deep dive.

Shared Brain: 500+ verified student Q&As. Semantic search. Network effects — every student makes it smarter.

Membean Automation: Auto-answers vocabulary questions. Extends to Quizlet, Khan Academy, Canvas, other platforms.

Real AP Question Generation: Per-course style guides (AP Bio = data tables, AP History = primary sources). Authentic stimuli. Real misconceptions as distractors. Difficulty matches actual exams.

What I Learned

RAG is hard but worth it. Parsing 38 College Board PDFs, chunking them cleanly, embedding for relevance — massive time investment. But now every question is actually standards-aligned. Knowt, Quizlet, ChatGPT don't have this.
Network effects matter. The shared brain feels small at 500 questions, but it's exponential growth. One more student = exponentially better answers for everyone.
High schoolers can build infrastructure. Vector DBs, embedding pipelines, semantic search — they're just libraries with clear documentation and careful thinking. Age doesn't matter. Skill does.
Shipping beats perfection. I cut FRQ grading and multi-model AI switching to ship on time. Done and shipped beats perfect and late.

How I Built It

The Stack:

Chrome Manifest V3 (extension)
Node.js/Express (backend)
Firebase Firestore (database + leaderboards)
Google Gemini 2.5 Flash (question generation)
Gemini Embedding API (semantic search)
Vectra (local vector database)
KaTeX (math rendering)
Web Speech API (voice tutor)
OpenAlex API (source verification)

The Challenges I Faced

Challenge 1: CORS & Private Network Access Chrome blocks content scripts from localhost. Solution: Route through background service worker using chrome.runtime.sendMessage. Took 2 days but it's the foundation everything runs on.

Challenge 2: Parsing 38 College Board PDFs CEDs have inconsistent structure. Regex failed. pdfParse broke. Solution: Custom chunking preserving CED codes. Worth the massive time investment.

Challenge 3: Semantic Search Relevance Asked about "ATP," got "atomic theory." Problem: generic embeddings. Solution: Better chunking, re-embedding with context, 0.72+ threshold filtering.

Challenge 4: Canvas New Quizzes Automation Canvas uses LTI iframes. Can't penetrate cross-origin. Solution: DOM manipulation at extension level instead of reaching into iframe.

Challenge 5: Rate Limits on Gemini 5000+ chunks hit free tier limits. Solution: Exponential backoff, resumable progress, batch processing.

Challenge 6: Question Quality First version: generic AI questions. Solution: Per-course style guides (AP Bio = data tables, AP History = primary sources). Authentic stimuli. Real misconceptions.

Challenge 7: Time Management Cut features to ship on time. Done and shipped beats perfect and late.

Why This Matters

Education shouldn't depend on money. A kid in rural Georgia shouldn't have worse test prep than a kid in Silicon Valley because their parents can't afford a tutor. The tutoring industry is a $2.5 billion gated garden. Pluto is the open door.

This isn't just a study app. It's a statement: If you have the internet and you have Pluto, you have world-class test prep. Period. For free. Forever. No hidden paywall. No "premium tier." No ads. Just students helping students, with AI making sure every answer is grounded in real curriculum.