X-RAY EYES! MULTIPLICATION MAGIC

Hi All,

This is not a big time math lesson, but kids love a good magic trick they can do, so here it is. This one uses the sevens times table and is a snap to learn.

*Tell students that if they roll a pair of dice you will be able to tell them the total of all the top numbers and bottom numbers (without looking at the bottom) because of your "x-ray eyes."

*The secret is that on any die, the top number and the bottom number always equal 7. Roll two dice and the total is going to be 14. Roll three dice and it will be 21. Four dice will be 28, and so on through the 7 times table.

*Begin with students rolling two dice, then three, then four, and let them use as many as you have available. See if they can figure out the trick.

*Once they figure it out (or you reveal it), they can practice and then take their "multiplying magic show" on the road and share it with others.

Simple, but fun. Oh, and keep the dice handy, on Thursday we'll get "Deeper with Dice."

All the best,
Bob

Adapted from Mathemagic by Raymond Blum (Sterling, 1991)

Comments

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