The Stacks

Notes worth studying from.

Every topic of AP Computer Science Principles and AP Computer Science A, written out in plain language, in the order the College Board teaches it — no ads, no login, no paywall.

Current AP Courses

AP Computer Science Principles 5 Big Ideas · 35 topics · open AP Computer Science A 4 units · 53 topics · open

How to use this

Both courses follow the College Board's Course and Exam Description exactly — every numbered topic is its own page with notes, a worked example, an exam tip, and practice questions with answers. Use the search box in the sidebar to jump straight to a topic, and the switches below it for dark mode or a color-blind-friendly palette.