Sequence 1 · Topic 3.10 Lists
Every Item Counts: Traversing a List
One complete learning sequence for AP CSP Topic 3.10 Lists, using 3.6 Conditionals and 3.8 Iteration. It is the first sequence on this site. It does not cover the whole course, and there are no AP score predictions.
By the end you can
- Trace a complete traversal and record how an accumulator changes after every element.
- Explain the difference between a complete and a partial traversal, and when each is correct.
- Choose boundary test cases that expose ≥ versus > errors, misplaced resets and early returns.
- Write and repair a procedure that counts list elements meeting a condition.
The sequence
- About 35 min1. Worked lessonRead two worked traces, then four common errors and how to catch each one.
- About 30 min2. Trace investigationPredict first, then step through four versions of one procedure and hunt for the tests that expose bugs.
- About 15 min3. Diagnostic checkFive practice questions with a rationale for every option and a pointer back to what to review.
- About 20 min4. Transfer reassessmentFive new questions in an unfamiliar context, for after review.
- About 50 min5. Class assignmentFive written prompts your teacher assigns in your class. Your answers save as cloud drafts, you submit them, and your teacher returns feedback. Students who aren't in a class can still do parts 1–4.
How this works
The investigation steps through four fixed pseudocode procedures. It is a simulation, not a code runner, so nothing you type is executed. Practice checks are self-checks that aren't saved or sent to anyone. Only the class assignment is saved and seen by your teacher.
Teachers: the teacher guide (timing, differentiation, rubric and model answers) needs an approved teacher account.