This challenge is to find as many ways as possible of making 12 using three number cards and the add, subtract and multiply signs.

Can you put the numbers 1 to 9 in the diagram so that the difference between each pair of joined numbers is odd?

Investigation looking at possibilities when adding the digits from 1 to 5.

A development of the 'Caterpillar investigation' but using multiples of 10. Great for practising addition.