This video helps students practice subtraction facts where you subtract from 13, such as 13 − 5 and 13 − 7. For that, we use both fact families with 13, and a NUMBER RAINBOW.
In the number rainbow, we connect two numbers with an arc if their sum is 13. This visual tool clearly shows students how the numbers are paired to make 13.
We also briefly go through all the fact families with single-digit numbers where the sum is 13 (one with 3 + 10, another with 4 + 9, then one with 5 + 8, and one more with 6 + 7).
Lastly I drill the viewers with the subtraction facts — Mathy joins in that also! I pause for a little while to let children answer the facts — thus this video can take the place of drilling by a teacher.
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Fact families — free online practice
Number rainbow & fact families with 11
Number rainbow & fact families with 12
Number rainbow & fact families with 14
Math Mammoth Grade 2 curriculum