A great way to get your children interested and curious about the power of algebra is through fun and freely available activities involving what first appears to be mind reading.

Let’s have a go!

Think of a number.

Add one to your answer.

Double it.

Take away 3.

Add the number you first thought of.

Add 7.

Divide by 3.

Now take away the number you first thought of.

I’m now reading your mind………

Your final result is 2!


Are you intrigued? You might be wondering how this works. Try it with your kids. Try it as a family or even with friends.

Here is a great website to try heaps more: http://coolmath.com/math-mind-readers/index.html

Set your kids up in front of this website with a piece of paper and a pen, and see if they can start to explain how the computer seems to be reading their mind.

This is how I began the topic of solving algebraic linear equations with my Year 7 classes last week. And it sure did get them excited, curious and keen to understand how this works.

We talked about the “maths magic” going on behind the scenes, and how algebraic simplification and solving equations were involved. I didn’t explain to them how it works just yet. With their interest piqued we are now learning about constructing and solving equations using flowcharts and methods of inverse operations. With these tools under our belt we will go back and construct the process algebraically and then examine how the mind reading is no mind reading at all!

So how do these tricks work? This video explanation is not only powerful, it is also a great non-threatening, pre-algebra way to explore these tricks with your kids and see if they can describe through drawings, how each trick works. At the end of the video the instructor develops algebraic notation, and if your child feels ready to take it to this next step then you might like to explore this with them.

Do you have a “maths magic” trick to share?

Photo credit: QnD2011 / Foter / Creative Commons Attribution-NonCommercial-NoDerivs 2.0 Generic (CC BY-NC-ND 2.0)