Math › Grades 1–3 › Fact families

What is a fact family?

A fact family is a set of three numbers and the four facts they make. 3, 7 and 10 give you 3 + 7, 7 + 3, 10 − 3 and 10 − 7. Learn one fact, and you get the other three.

Grades 1–3Common Core 1.OA.B.4 · 3.OA.B.6Also called: related facts60-second readEn español
10 3 7
  • The top number is the total (or, for multiplication, the product).
  • The bottom numbers are the parts (or factors).
  • 3 + 7 = 10, 7 + 3 = 10, 10 − 3 = 7, 10 − 7 = 3
Three numbers, four facts.

Why schools teach it

Subtraction and division come free

First graders learn subtraction as a missing-number problem: 10 − 3 is "what plus 3 makes 10?" (1.OA.B.4). A child who knows the family doesn't have to memorize subtraction as a separate list.

The same thing happens in 3rd grade with multiplication. 24 ÷ 6 is taught as "what times 6 is 24?" (3.OA.B.6), so a solid 6 × 4 gives you the division fact for free.

At the kitchen table

What to say, and what to skip

Say this

  • Which number is the biggest? Where does it go?
  • If 3 + 7 = 10, what is 10 − 7?Let them use the family instead of counting back.
  • Can you make a take-away fact from these three numbers?
  • What times 6 makes 24?Asking division this way is exactly how 3rd grade teaches it.

Skip this

  • Drilling subtraction facts as their own list.The family does that work. Practise the families instead.
  • Subtraction is a totally different thing.Showing it as the opposite of adding is the whole point.
  • Mixing numbers from two families.3, 7 and 11 don't make a family. Check the top number is really the total.

See it in action

Building the family for 6, 8 and 14

  1. Find the biggest number. That's the total.

    14
  2. Write the two adding facts

    6 + 8 = 14,  8 + 6 = 14
  3. Write the two take-away facts

    14 − 6 = 8,  14 − 8 = 6

When a child answers 14 − 6 quickly because they "know 6 + 8," the family is working.

Free practice sheet

Make a fact family sheet

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Parents also ask

Why do doubles only have two facts?

With 5, 5 and 10, the two adding facts are the same (5 + 5) and so are the take-away facts (10 − 5). Most worksheets skip doubles for this reason.

Is a fact family the same as a number bond?

They're cousins. A number bond is the picture of the whole and its parts. A fact family is the four equations that picture gives you.

Does it work for multiplication?

Yes. 4, 6 and 24 give 4 × 6, 6 × 4, 24 ÷ 4 and 24 ÷ 6.

Some worksheets use a house instead of a triangle. Does it matter?

No. Triangle, house or circles, the idea is the same three numbers.

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