This activity from the Computer Science for Fun (CS4FN) team at QMUL is an introduction to algorithms suitable for those in upper primary school. A ‘self-working’ magic trick is shown – this is a trick that works every time, as long as the process is followed exactly. No understanding of the trick is needed by the ‘magician’ – this is similar to how a machine can ‘solve’ problems using an algorithm with no understanding of what it is doing.
After explaining how to do the trick, this teacher guide explains the mathematical rules which make it work and draw parallels to writing computer programs.
Extension activities are provided, including writing down the algorithm and the challenges of making mental models.