Math Magic Trick

This trick is an extraordinary introduction to the power of algebraic thinking, and a reminder of what makes algebra so awe-inspiring.

A video Launch for this lesson is available in two parts. PDF of the lesson is below the videos.

Part 1. When using as a class launch, stop at 2:45 and let the class come up try to find their own counterexamples.

Part 2 – the solution to the magic trick.

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Lesson Notes

Comments 1

  1. Matt Notary

    Dan – I came across your site today after reading an article that mentioned it. Just wanted to say I have enjoyed looking at some of the lessons and I appreciate what you are doing! I am a middle school math teacher, and I have used a number trick that is similar to this one on the first day of my algebra class for many years now. It’s always a lot of fun and helps students start to grasp the power of algebra.

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