Revising subtracting small numbers with the help of a number line.

This time there?s a number square to help with subtraction. It?s interesting to see how children use the number square to help them.

Use knowledge to subtract a single digit from a teen number quickly and efficiently. Rather than just counting up in ones, look for two steps, firstly to ten and then to the number.

A look at the inverse relationship between addition and subtraction.