Here is a simple activity to get children thinking. I like starting points for problems that open up all sorts of possibilities - even better if they can lead the children on to making up their own questions. This is a good example of that, with an accessible starting point for all abilities from Y1-6.
Provide a selection of different regular shapes made from card - equilateral triangles, squares, regular pentagons and regular hexagons. Make them large enough to write a number in the centre with space to write other numbers in each corner.
Write a number in the centre of a shape and ask the children in pairs to put numbers on the corners so that they add up to the number in the centre. For example, if 9 is in the centre of a square, children can work out possible corner numbers. For older children, 2-digit numbers, decimals or fractions could be used.
Write a number in the centre of a shape and ask the children in pairs to put numbers on the corners so that they add up to the number in the centre. For example, if 9 is in the centre of a square, children can work out possible corner numbers. For older children, 2-digit numbers, decimals or fractions could be used.
It is good to look at the strategies they use as they work them out. Do they put on small numbers, total them and find the difference? Do they keep calculating after each number is added? I have heard some great discussions from 8-year olds trying to work out how close they can get before deciding on the final number. Once they have tried a few examples they can then have a go at putting in their own centre numbers.
