Fact families - addition and subtraction bonds to 20

Learning focus

Learn how part whole models can be used to understand fact families.

This lesson includes:

  • a catch-up quiz
  • two videos
  • two activities


To get started, let's see how well you know this topic already. Take the catch-up quiz below to find out.


Fact families

Watch this video all about creating a fact family.

White Rose Maths

Now, let’s have a look at this video about how a part whole model and a bar model can be used to understand a fact family.

White Rose Maths

Part whole models

A part whole model can be helpful when working out simple calculations. They are a visual representation of writing out number sentences and can help solve missing fact family numbers.

Have a look at this part whole model.

The model shows that the numbers 20, 12 and 8 are part of a fact family.

The number 20 is made of two parts, 12 and 8.

The diagram can help you work out possible number sentences in the fact family.

12 + 8 = 20

8 + 12 = 20

20 - 8 = 12

20 - 12 = 8


Activity 1

Can you complete the questions in this activity sheet?

Fact families

Check here for the answer sheet

Activity 2

Have a go at this worksheet about using fact families and number bonds to answer sums. You can print it out or write your answers on a sheet of paper.

Addition and subtraction facts to 20

Check here for the answer sheet

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