If you've got some subtraction specialists in your class and they want to pit their skills against some more testing, open-ended problem-solving questions, grab them this Year 4 Subtract Two 4-Digit Numbers - One Exchange challenge activity! It comes with two questions designed to encourage children to think, discuss and apply their understanding in different ways to problems which require a little more thought.

The resource works wonderfully as a group task, but could also be done alone or with an adult as a discussion partner, at home or in school. The pack comes with an example answer sheet, to help you or your pupils to easily check if their answers are on the right lines.