A-Level Computer Science · Syllabus 19.2
Recursion
Coursebook chapter 19: Computational thinking and problem solving
No chapter review yet. It is on its way.
InteractiveRecursion: Base Cases, the Call Stack and Unwinding19.2 Seven step-by-step call stack and call tree animations with pseudocode and Python, labs, practice and 20 exam-style questions.Open →
Extra activities that deepen understanding or give more support. Shown in syllabus order.
No extra resources for this chapter yet.
InteractiveRecursion in Action: Compound Interest and Its Trace Table19.2 A compound interest function traced step by step: call stack and trace table animations, a check of Table 19.29, labs, practice and every past-paper recursion question 2021 to 2026.Open →
InteractiveRecursion in Action: The Fibonacci Sequence19.2 Double recursion: Fib(n) as a call stack and call tree, the M/J 2023 trace table, call counts, why the simple version is slow, labs, practice and exam questions.Open →
InteractiveRecursion in Action: Binary Tree Traversal19.2 In-order, pre-order and post-order traversal and a recursive tree search, traced call by call, with a tree walker lab, practice and exam questions.Open →
InteractiveRecursion in Action: Binary Search19.2 Recursive binary search on a sorted array: the range halving call by call, the O/N 2025 Paper 4 question, call counts, labs, practice and exam questions.Open →
InteractiveRecursion in Action: Lists and Strings, One Item at a Time19.2 Totals, counts and vowels: the first-item-then-the-rest pattern, loop to recursion rewrites, every Paper 4 list and string recursion question, labs and practice.Open →
Deleted: hidden from students and progress. Only you can see this tab.