Fact families - addition and subtraction bonds to 20
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.
Watch this video all about creating a fact family.
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.
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
Can you complete the questions in this activity sheet?
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.
There's more to learn
Have a look at these other resources.