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Practice subtracting by counting down from the larger number. Talk about how “take away” and “difference” are two good models for subtraction.

Storybook properties

This has skip counting, shapes, and comparisons.

Activities properties

These involve comparing, adding, and subtracting.

Two kinds of subtraction

There are two models for subtraction, and both are important. The first is taking away. If you are asked to subtract 3 things from 9 things, you will probably think of this as taking away or removing 3 of the things. The second model involves difference. The difference between two numbers is the distance between them . If you are asked to subtract 7 from 9, you are likely to do this be finding how far apart they are, what their difference is.

Both understandings of subtraction are needed and are useful. For mental arithmetic, having a choice of using take away or difference can make a big difference in the ease of the calculation. Additionally, some problems are more naturally understood as take away or difference problems.

Counting down

Counting down is a natural way to do take away. Use 9 – 3 as an example of subtracting by counting down.

As with adding, your child may want to initially do this using their fingers, and that is fine. Say “9” and have a closed fist to indicate 0. Next, count down “8, 7, 6” and raise one finger with each number. Stop at 6, when three fingers have been raised.

Over time, using fingers with small subtraction problems will become less necessary. Your child will start to mentally see the change of 3 in going from 9 to 6, and will no longer need to use fingers – just as they no longer need fingers for subtracting 1 or 2.

Subtracting 1 to 4

With practice, your child will build up speed using this approach for subtracting the numbers from 1 to 4. Take your time and make sure everyone enjoys the process.