## 21 things every computing teacher should try:

Teach with magic!

*Reading time:*5 minutes

Using magic tricks to teach computational thinking

You may be asking the question: “What do magic tricks have to do with computational thinking?”. The simplest answer is that all magic tricks are based on an algorithm (sequence of step-by-step instructions.) Similar to a recipe or set of directions, if any of the steps are wrong or are not clearly explained, the trick is likely to fail. However, as well as introducing students to algorithm design, magic tricks can also help students understand other computational theory elements such as Abstraction (), Pattern recognition (looking for common patterns in the trick) and Decomposition (breaking down the magic trick to help understand it better).

**The trick**

Big thanks to Mark Dorling (Digital School House) for this trick. The purpose of card trick is to teach pupils about sequencing and modelling a sequence of instructions.

Although not required for the trick too work, the story helps the students remember the sequence of the trick. I suggest following the video exactly, including the Harry Potter story! The reason I suggest using the story is that I find students remember the trick better if they can link it to the story.

At the end of the trick, divide the students into small teams and give each team a set of cards. Next, challenge the students to repeat the trick and, once they have solved the trick, produce step-by-step instructions. (

**Try to encourage the students to write down every step – this is key for the next part).**

*Note:***For those students who find this task difficult, you can let them watch the video again. I also find that doing the trick with all the cards face up also helps.**

*Tip:*As the teams write their step-by-step instructions, circle around the class and attempt to follow their instructions: the key here is to follow the instructions exactly – emphasising any imprecise/vague instructions (as if you were a robot). For example, if a student writes down the instruction “Sort the cards into four suits”, do this for every card in the pack - not just the cards 7, 8, 9 and 10, or if a student writes down the instruction “Put the cards in order”, sort some of the cards in descending order 10, 9, 8, 7 and some in ascending order 7, 8, 9, 10.

Hopefully this will generate discussion about need for detailed / precise instructions. Draw out answers such as “The instructions were too vague” or “The instructions were not specific”. Explain to students that computers (such as robots) can’t think for themselves therefore, when programming a computer, they must make sure that their instructions are precise.

**How to get started**

The good news is that you don’t have to be a professional magician to perform these tricks – nor do you need to join the magic circle! Thankfully, there are a number of websites that will show you how to perform these simple tricks as well as show you how to incorporate these tricks into your lesson plans.

Below is a collection of websites dedicated to the use of magic in the classroom:

*The magic of…*The magic of series is a collection of resources, produced by Queen Mary University of London, which aims to support teachers in the use of magic in the classroom to engage and inspire learners. All the resources are linked to the national curriculum and cover principles found in subjects such as Mathematics and Computing. Each resource contains a selection of hand-picked magic tricks and includes step-by-step instructions as well as explanations of how the tricks work.

Websites:

- The magic of Computing: http://www.cs4fn.org/magic/
- The magic of Mathematics: http://www.qmul.ac.uk/mathsmagic/

*Maths Made Magic*A handbook of mathematical based magical tricks intended for use in the classroom. These magic tricks have been mapped to the KS4 curriculum and cover a diverse range of mathematical concepts from probability to Pythagoras. The handbook also contains step-by-step instructions for performing each trick as well as details of the mathematical principle behind the trick.

Website: http://www.qmul.ac.uk/mathsmagic/

*The manual of mathematical magic*As well as showing you how to perform a variety of mathematical magical tricks, the book explores the mathematics behind each trick and explains how that same mathematics is used in the real world. It also looks at the varied and exciting sorts of jobs that make use of the mathematics powering your magic. All the tricks are self-working, which means there is no need to know any clever sleight of hand, and cover a range of mathematical concepts from addition to algebra.

Website: http://mathematicalmagic.com/

*Illusioneering*A book containing easy to do magic tricks based on scientific principles covering chemistry, physics, engineering and mathematics. Each trick includes step-by-step instructions as well as tips for performing the trick.

Website: http://illusioneering.org/ - See more at: http://teachwithict.weebly.com/tl-blog/the-magic-of-teaching#sthash.smrvytxj.dpuf