Fact Families - addition & subtraction - video lesson for 1st grade math
In this 1st grade math lesson, we write FACT FAMILIES using small numbers. A "fact family" consists of two additions and two subtractions that use the same three numbers. It's the same concept as NUMBER BONDS. For example, 2 + 6 = 8, 6 + 2 = 8, 8 − 2 = 6, and 8 − 6 = 2 makes up a fact family (two addition facts plus two subtraction facts).
If you're given just ONE of those facts (either addition or subtraction), you can write the entire fact family, and that is what we practice in the middle part of the lesson.
Lastly, we solve two word problems that involve bicycle and tricycle wheels — DRAWING the problem helps a lot here!
If you cannot see the video above, click here for an alternative video player.
See also
Fact families — free online practice
The concept of "how many more" — video lesson for 1st grade math
Math Mammoth Grade 1 curriculum