Active Number is a whole-school approach to the teaching and understanding of number and operations to primary aged pupils. It uses the principles of mnemonics, intended to assist the memory, to develop “mastery”, providing a deepened understanding of number and calculation using the four operations. It is proven that learning gained by doing through interacting with others, supports retention. Using images, actions and verbal reasoning the child’s learning develops using a spiral approach. The Active Number has proven impact within both the lead school and beyond and is also supported by the current EEF guidance reports for supporting mathematics in key stages two and three.