Why not try this display in your classroom or in a corridor. It is sure to get people stopping to try and work the answer out.
What you need
A set of coloured circles to make a caterpillar with. A couple of sets of numbers from 20 to 0 or whatever number you want to start from.
How it works
There is a pattern to follow when trying to complete this challenge.
Pick the number on one of the caterpillar's heads eg. 13
If this number is an even number divide it by 2 to get your next number in the row. Put that number on the next circle.
If the first number is an odd number add 1 and then divide it by 2 to get your next number. eg. 13 + 1 = 14 then divide by 2 .
This gives you your second number eg. 7
If this number is even then divide it by 2 again.
If it is odd, add 1 and then divide it by 2 eg 7 + 1 = 8, divide by 2 = 4
Continue this pattern until you complete the caterpillar. Your final number will always be the same.