I teach AP Computer Science A, and CompSci.rocks grew out of the notes, worked examples, and small tools I kept building for my own classroom. Eventually it made more sense to put all of it in one place where other teachers and students could use it too.

What's here

• AP CSA free-response solutions. Every year, College Board releases the free-response questions a couple of days after the exam, and every year I work through them and write up a solution. You'll find walkthroughs going back to when the exam switched to Java, with an explanation of the reasoning behind each answer, not just the code.
• Java tutorials. Short, focused write-ups on the algorithms and language features that come up constantly in an intro Java course — things like finding a minimum or maximum in an array, Math.random(), and other patterns worth actually understanding rather than memorizing.
• Grading tools. A handful of calculators for the parts of teaching that don't need to be done by hand: converting raw scores to a grade, curving a set of test results, or figuring out what a student needs on a final exam.
• Small projects. A couple of programming tools I've built and open-sourced along the way.

Why I post solutions

I go back and forth on this one. Having FRQ solutions publicly available means a student could find a working answer without doing the work themselves. But having solutions to study is also just a normal, useful part of learning — and there are already plenty of other sites posting the same solutions, so I'd rather mine be good.

Get in touch

Questions, corrections, or something not working the way it should? Email site@compsci.rocks.