How to use an AP Computer Science A practice test

What this exam actually asks of you

The AP Computer Science A multiple-choice section is 42 questions in 90 minutes and carries 55% of your final grade. The rest is four free-response coding questions in 90 minutes: methods and control structures, class design, array and ArrayList work, and 2D arrays, which a computer cannot mark. A practice sitting covers the half that can be marked exactly.

The mistake that ruins the result

Practicing by writing programs. Writing code and reading somebody else's are different skills, and this section is entirely the second one.

How to sit it

All 42 questions in one 90-minute block, no pauses. The real exam hands you the whole clock and lets you spend it, so a practice run broken into units removes the only decision the section actually asks you to make.

What to do the day after

Go back to every wrong answer and trace the loop by hand, writing each variable down the margin. Most errors here are tracing slips rather than misunderstandings.

What a practice test owes you

An AP grade is a 1 to 5 cut from a composite whose boundaries move every year, so a practice percentage on AP Computer Science A converts to nothing. What converts is knowing which questions you got wrong and why.

Our AP bank holds 544 questions and 1,632 wrong answers, and every one of those wrong answers carries its own sentence saying what a student who picked it was probably thinking. Not one is left bare, and a build of our site fails if that stops being true. For AP Computer Science A that matters because the wrong options are written to be the answer a student gives when they have half the idea, which is not something a score can tell you.

We also measure whether the paper can be beaten without being read. On our AP exams the best any length-based strategy scores is 38%, against the 25% that pure guessing gives. A practice test where picking the longest option beats guessing is measuring the person who wrote it, not your child.

At more than two minutes a question this is the most generous clock of any AP we publish, which is exactly why students sink ten minutes into one array problem.

Where to sit one

We publish two AP Computer Science A forms with no questions shared between them, so a second sitting measures what you learned rather than what you remembered. A free sample is on the samples page, and it needs no account.

More on this exam: the full AP Computer Science A guide, what is on it, pacing the section.

Common questions

How long should a AP Computer Science A practice test take?

42 questions in 90 minutes for the multiple-choice section, which is 55% of the grade. The free-response half is separate and needs a human reader.

Should a AP Computer Science A practice test be timed?

Yes, the full 90 minutes in one block. The real exam hands you the whole clock and lets you decide how to spend it, and that decision is most of the difficulty.

Is the score the useful part of a AP Computer Science A practice test?

No, the reasons are. Every one of the 1,632 wrong answers in our AP bank carries a sentence saying what a student who picked it was probably thinking, and for AP Computer Science A that is what turns a list of misses into a plan.

How often should we sit a AP Computer Science A practice test?

Twice: once early enough that there is time to fix what it shows, and once close enough to May to check that you did.