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Step through linear search, binary search, bubble sort, and merge sort and see exactly how each algorithm works.
How to use it
Understanding how a search or sort algorithm works from a written description alone is difficult. This tool makes every step visible — each comparison, each elimination, each swap — so students can follow the logic at their own pace rather than trying to picture it from a textbook.
Linear search checks each element in turn from left to right. Binary search calculates a midpoint, compares it to the target, and eliminates half the list with every step. Bubble sort repeatedly compares adjacent pairs, swapping them when they are out of order, until a full pass produces no swaps. Each step is explained in plain language using the same terminology expected in GCSE exam answers.
The step explanations are written in the language of GCSE mark schemes — "checking index 0", "middle element is index 3", "no swap needed, moving right". Working through an algorithm step by step is exactly the kind of trace question that appears in AQA, OCR, and Edexcel Computer Science papers. Use this tool to practise before an exam or to check your own manual traces.
Linear search, binary search, bubble sort, and merge sort are all required content in GCSE Computer Science specifications. This tool covers all four in one place, so students can practise every algorithm they need for the exam.
Python Coach includes 27 lessons and 195 challenges — from a first print statement through to functions and file handling, all mapped to the GCSE specification.