11. Sorting Unplugged

An inspiring unplugged session on teaching computing for teachers.


In this workshop we demonstrate some practical and powerful ways to teach basic sort algorithms using unplugged methods. Students act as an array of values to be sorted, with others as loop variables. Together you gradually work out a sort algorithm, Bubblesort, that works by doing lots of passes over the array. The students also work out how to improve the algorithm, and you explore how much faster the improved version is. You develop the code as the algorithm is developed. A further activity shows how this can be improved upon even more using divide and conquer techniques, again that are acted out, in a way that shows both how divide and conquer works but also why it is so much faster. Finally you demonstrate an almost magical algorithm that sorts a pile of cards in just a few steps.

Session material
This session will cover:

  • Sort Algorithms: Bubblesort, Mergesort, Quicksort and Radix Sorting
  • Simple, memorable ways to teach sort algorithms.
  • Efficiency of algorithms
  • Why divide and conquer problem solving is so powerful
  • A practical, physical use of binary

Activities are suitable for all age groups and can be adapted to fit your teaching needs.

Paul Curzon is a Professor of Computer Science at Queen Mary University of London. He runs the cs4fn ‘Computer Science for Fun’ (cs4fn) project, www.cs4fn.org. It aims to inspire school students about computer science through a series of free magazines, website and school shows. He regularly gives such shows around the UK as well as continuous professional development talks to teachers about the cs4fn approach to teaching. He is Director of the Teaching London Computing Project. He was made a UK National Teaching Fellow in 2010 in recognition of his excellence in teaching and outreach, was a finalist in the 2009 Times Higher Education Innovative Teacher of the year award and has twice won the student nominated Queen Mary University of London award for excellence in teaching.

This session comes with slides linked activity sheets, props and ‘story’ write-ups that you can download:

This is a self-contained evening interactive seminar session. It will last 60-90 minutes plus time for networking.  For our programme of longer courses for teachers please see CPD courses.

Similar sessions on other topics
Want to get up to speed on computing concepts like computational thinking or ideas for how to teach computing in a fun, inspiring way? Teaching London Computing with cs4fn run as series of free one off sessions for teachers of ICT and computing such as this one.

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