AP CSP vs AP CSA: Which Should You Take First?

The standard advice is so widespread that most families never question it. Take AP Computer Science Principles in Grade 10 as the gentle introduction, then AP Computer Science A in Grade 11 or 12 once the student has some confidence. It sounds obviously right. For a large number of students it is exactly backwards, and the 2026 results make the case better than any argument could.

In May 2026, 10 per cent of Principles candidates scored a 5. In the same month, 25 per cent of Computer Science A candidates scored a 5. Both are College Board's preliminary numbers for that year, published ahead of the final counts. The course everyone calls the hard one is two and a half times more likely to produce the top grade.

The two distributions, side by side

Read the middle row. Principles sends 30 per cent of its candidates home with a 3, more than any other grade. It is a course that reliably gets students to a pass and rarely past it. Computer Science A is the opposite: the 3 is its rarest outcome after the 2. It sorts, hard, and it sorts on one thing.

What a year in each course actually looks like

Difficulty is the wrong axis anyway. The useful question is what kind of work the student will be doing for a year, because that is what determines whether they finish it.

Principles is built around the Create performance task. Students get at least nine hours of class time to build a program of their own choosing, then submit the code, a video of it running, and a Personalized Project Reference through the AP Digital Portfolio by the end of April. The exam itself is 70 multiple choice questions in 120 minutes for 70 per cent of the score, and a 60 minute written response section for the other 30 per cent, in which students answer questions about their own program with the reference document in front of them.

Computer Science A has no project and nothing to submit. Four units, Java throughout, and a three hour exam split into 42 multiple choice questions at 55 per cent and four typed free response questions at 45 per cent. The four written questions are always the same four types: methods and control structures, class design, data analysis with ArrayList, and 2D arrays.

The same task in both languages

Here is a way to feel the difference rather than read about it. The Create task requires a program containing six specific things: a procedure you wrote that takes a parameter which affects what it does, a call to that procedure, a list, a use of that list, selection, and iteration. This is the whole of it, in Python.

def passing(scores, cutoff):
    kept = []
    for s in scores:
        if s >= cutoff:
            kept.append(s)
    return kept


marks = [72, 45, 91, 58, 30]
print(passing(marks, 50))
print(passing(marks, 90))

[72, 91, 58]
[91]

That program, or something no more complicated than it wrapped in a purpose a student can defend, meets the technical bar. What Principles then asks is whether the student can explain in writing why the procedure needs its parameter, what would break without the loop, and how they tested it. The programming is the small part.

Now the same task as Computer Science A would ask for it.

import java.util.ArrayList;
import java.util.List;

public class Passing {
    public static List<Integer> passing(List<Integer> scores, int cutoff) {
        List<Integer> kept = new ArrayList<Integer>();
        for (int s : scores) {
            if (s >= cutoff) {
                kept.add(s);
            }
        }
        return kept;
    }

    public static void main(String[] args) {
        List<Integer> marks = List.of(72, 45, 91, 58, 30);
        System.out.println(passing(marks, 50));
        System.out.println(passing(marks, 90));
    }
}

[72, 91, 58]
[91]

Identical output. Roughly three times the syntax, all of it typed from memory in a plain editor with no compiler and nothing underlining a missing semicolon. That is the actual difference between the two courses, and any student can decide which of those two pages they would rather spend a year on.

Which one to take first

Here is the question we ask on the first free class, and it predicts the right order better than any test score: has this student ever written a program nobody asked them to write? A game, a bot, a script to rename files, anything at all that was their own idea.

• If yes, take Computer Science A first. They will find Principles slow, and slow is the enemy of a fifteen year old's interest. Doing the Java year while the enthusiasm is live gets a 5 on the record early, and Principles afterwards becomes a comfortable second AP rather than a year of waiting.
• If not yet, take Principles first. Not because it is easier, but because it builds two things the Java year assumes: the vocabulary to talk about programs, and the habit of finishing a project. A student who arrives at Computer Science A with those already in place has a far better shot at the 25 per cent than one arriving cold.
• If the school only offers one, take that one. A well taught course with a teacher who knows the student beats the theoretically optimal choice studied alone, every time.

Two things to sanity check before deciding. The exams are in the same window in May, so taking both in one year means preparing a project and a Java paper in the same spring, which is doable but not for a first year of programming. And credit policies differ from college to college, sometimes sharply, so it is worth ten minutes on the AP credit page of two or three colleges the student cares about before treating either course as a credit strategy.

The mistake that costs a grade in each

For Principles, it is leaving the Create task until March. The program has to be finished, filmed and documented before the deadline at the end of April, and a student who starts in March writes something they cannot explain under exam conditions six weeks later. Start it in the autumn, finish it by February, and spend the spring rehearsing the written responses about it.

For Computer Science A, it is treating the four free response questions as four unpredictable problems. They are four fixed types. A student who has written twenty classes to somebody else's written specification does not have to think on exam day, and the minutes that saves usually decide whether question 4 gets finished.

Nobody has ever regretted taking the Java course first because it was too hard. Plenty have drifted out of computing because the introductory course was too slow to hold them.

, What a decade of teaching both has taught us

How we teach both

Our AP Computer Science Principles coaching spends most of its time on the two things that decide the grade, which are the written responses about the student's own program and the reading heavy multiple choice, rather than on building an impressive project. Our AP Computer Science A classes spend most of theirs inside collections, because collections decide close to half of that paper.

Every class is live, one to one or in a batch of five to eight students, taught from India to students worldwide. The first class is free, no card is asked for, and the single most useful thing to bring to it is the honest answer to the question above about programs nobody asked for.

Frequently asked questions