Addition and subtraction

Investigate the different ways that fifteen schools could have given money in a charity fundraiser.

Try out this number trick. What happens with different starting numbers? What do you notice?

Throughout these challenges, the touching faces of any adjacent dice must have the same number. Can you find a way of making the total on the top come to each number from 11 to 18 inclusive?

When I fold a 0-20 number line, I end up with 'stacks' of numbers on top of each other. These challenges involve varying the length of the number line and investigating the 'stack totals'.

Watch this animation. What do you notice? What happens when you try more or fewer cubes in a bundle?

How many different differences can you make?

This task combines spatial awareness with addition and multiplication.

This challenge combines addition, multiplication, perseverance and even proof.