Calculus Lab

An interactive, intuition-first study site for AP Calculus AB and BC: live graphs you can drag and zoom, step-by-step worked examples, randomized practice with exact and symbolic answers, original free-response questions, and an exam builder. One site for both exams: choose AB or BC at the top of the menu and the BC-only parts step aside.

Unofficial study aid. Not affiliated with the College Board. AP and Advanced Placement are trademarks registered by the College Board.

What is inside

• 50 modules: a math toolkit, Units 1-8 (AB and BC), and a "BC only" section (integration techniques, Euler's method, logistic models, arc length, Unit 9 parametric/polar/vector, Unit 10 series).
• Each module: the idea, an assumption upgrade, a live lab, "Try this" predictions, a worked example, common mistakes, an explanation and check-yourself questions.
• Practice set (188 randomized problem generators), "Which method?" trainer, exam builder, mistakes queue, FRQ practice with point-by-point scoring.
• Reference drawer: derivatives, integrals, limits and series.

Build and test

python3 tools/mk.py   # regenerate module pages from tools/units/*.py
python3 build.py      # writes index.html (needs Python 3 and Node)
node tests/flow.js    # end-to-end flows (Playwright + Chromium)
N=400 node tests/audit.js
node tests/check.js [moduleId ...]

See CLAUDE.md for the layout and the rules that keep the site working. localStorage keys all start with calc-.

Part of Intulab, and installable as part of the Intulab app (works offline).

Report a mistake or something confusing with the Report an issue link on any page. It opens a pre-filled issue in the shared Intulab feedback tracker, labelled course:calc.

Privacy: progress stays in your browser (keys start with calc-); visits are counted anonymously with GoatCounter (no cookies). See the Privacy policy and Terms of use. © 2026 Jiarui Li. All rights reserved.