Sometimes, just subtracting can be enough of challenge, so doing it 'efficiently' is really something. We've created this Year 4 Efficient Subtraction activity to give children who may find efficient subtraction slightly challenging a little extra practice. It comes in the form of a game, and can be used in class or maybe as part of an intervention group. Instructions and a list of resources are aslo provided to ensure that any adult leading the task is efficiently prepared.