In Year 5 the children can build upon the different ways that the Mathematics Framework suggests for subtraction problems on paper. Each of these ways should build on their knowledge of mental strategies. All are equally good, but the ‘decomposition’ method is considered to be the most efficient. A key to all three methods is that the sum is set out in columns and that units should line up under units, tens under tens and so on. In Year 5, children will meet subtraction problems where the tens and hundreds boundary has to be crossed. Method 1: counting up This is called "counting up" and is a method very similar to mental subtraction which children are used to, whereby they count on to the next ten, hundred etc. Method 2:  subtracting hundreds and compensating This method works by taking away to the nearest hundred above and then adding the difference to compensate. The child needs to be very confident with mental subtraction from whole hundreds. Method 3: decomposition The more traditional method whereby if the units to be subtracted are larger than the original number then one ten is 'borrowed' from the tens column. Go to Written methods of subtraction in Year 5