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Subtraction Facts within 20

Get fast at a − b — count back, count up, and use your bonds

Set the start and how many to take away, then empty the ten-frame one dot at a time.

Start at

13

Take away

8

138 = ?

Counters left

13

Count back: Start at 13, step back 8 → you land on 5.

Count up: From 8 count up to 13: that is 5 steps. So 13 − 8 = 5.