AQA 8525 3.1.4: Sorting algorithms
The free BugBot lessons that teach this point, a robot to try it on, and the past-paper questions that test it.
What it covers
Binary search needs sorted data, and so do leaderboards, timetables and the robot's "nearest first" lists. Sorting puts items in order. This lesson and the next two meet the three sorting algorithms on the GCSE specifications, and this one you can hear: the robot plays a list of notes, and as the sort works the tune turns into a scale.
- The algorithm
- In Python
- Hear it sort
- How much work it does
Or do it in the simulator, with tasks that mark themselves
Lessons that teach it
- F5.7 Bubble sort Algorithms
Passes and swaps, stopping early, and hearing a tune become a scale. - F5.8 Insertion sort Algorithms
Building a sorted part one item at a time, on the robot's readings.
Try it on a robot
The task from F5.7 Bubble sort, running here. Change the program and press Run.
Past paper questions on this
Real exam questions that test this, each worked through with a program you can run.
- AQA 8525 June 2025 Paper 1, Question 6: Show a bubble sort and a merge, compare them, and justify a binary search 10 marks
- AQA 8525 June 2022 Paper 1, Question 12: Trace a bubble sort on three items 8 marks
- AQA 8525 Sample Paper 1, Question 7: A bubble sort with a swapsMade flag: data type, identifiers, and a trace table 10 marks
- OCR J277 June 2023 Paper 2, Question 3: Insertion sort: temp, the inner loop, and bubble sort compared 8 marks
- OCR J277 Sample Paper 2, Question 6: Show a bubble sort on words and a binary search for zebra 8 marks
- Edexcel 1CP2 June 2025 Paper 1, Question 5(d), (e): Computational thinking: best and worst cases, and a binary search table for a missing value 10 marks
The specification is AQA's own document; this page says which of our lessons teach point 3.1.4 and is not endorsed by the board.