Tell a story of someone having trouble looking after two dogs who will not do what they are told. Then they get given two more dogs to look after - now they have four and they have ‘double trouble’! What about if they have three dogs - how many would be double trouble? We asked the children to model doubling numbers up to five on their fingers and to select images to represent in other ways using various resources. We then asked questions such as 'What do you have to do when you double?' 'How do you know a number is a double?' 'What do you notice about the numbers and their patterns?'