Related Facts
We use addition to help us subtract. If the problem to be solved is 8-5= students can think,
"I know 5+3 is 8 so 8-5=3.
Fact Families - Build a house. Fill it with a family of numbers.
5+3=8
3+5=8
8-5=3
8-3=5
Tools to fact fluency
We make triangle flash cards that work for addition and subtraction. Each number in the fact family go in a corner of the triangle. The largest number (the whole) is written at the top. The other two numbers (the parts) will be written in the bottom corners. Depending on which number is covered you can practice addition or subtraction.
8
3 5
Count back from the whole on a number line. OR Count up from the part you know.
3 4 5 6 7 8
