New

Year 2

Explain that the addends can be added in any order

I can explain that the addends can be added in any order.

Download all resources

Share activities with pupils

New

Year 2

Explain that the addends can be added in any order

I can explain that the addends can be added in any order.

Download all resources

Share activities with pupils

These resources will be removed by end of Summer Term 2025.

Switch to our new teaching resources now - designed by teachers and leading subject experts, and tested in classrooms.

View new resources

Slide deck

Download slide deck

Skip slide deck

Lesson details

Key learning points

When we add three numbers, the sum will be the same whichever pair of addends we add first.
The order of the addends can change and the sum will stay the same.

Keywords

Addends - Any numbers that are added together.
Efficient - Not wasting time or effort. An efficient strategy is one we can carry out easily.
Strategy - A plan or method to achieve a specific goal.

Common misconception

Children may not understand that either pair of addends can be added first and the sum will remain the same.

Use concrete materials to represent the addends for children to explore, discussing what is the same (the addends) and what is different (the pair being added first).

This is the first time they will be exploring the associative law. Children do not need to know the term 'associative law', they just need to understand that they can add any pair of numbers first and that this will not change the sum.

Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on

Open Government Licence version 3.0

except where otherwise stated. See Oak's terms & conditions (Collection 2).

Lesson video

Skip lesson video

Worksheet

Download worksheet

Skip worksheet

Starter quiz

Download starter quiz

6 Questions

Q1.

Look at each expression and match it to the correct description.

Correct Answer:3 + 6,less than 10

less than 10

Correct Answer:7 + 3,equal to 10

equal to 10

Correct Answer:6 + 6,greater than 10

greater than 10

Q2.

Match the addition expressions that are equal to each other.

Correct Answer:2 + 5,5 + 2

5 + 2

Correct Answer:7 + 4,4 + 7

4 + 7

Correct Answer:1 + 8,8 + 1

8 + 1

Correct Answer:10 + 3,3 + 10

3 + 10

Q3.

Which of the equations could not represent this ten frame?

4 + 2 = 6

6 = 2 + 4

6 - 4 = 2

Correct answer: 6 = 4 - 2

Q4.

Look at this ten frame. Altogether there are 9 counters. The addends are 2, 4 and

Correct Answer: 3

Q5.

Match each number to the correct part of the model.

Correct Answer:1,addend

addend

Correct Answer:8,sum of the addends

sum of the addends

Correct Answer:3,addend

addend

Correct Answer:4,addend

addend

Q6.

Which equation is shown on this number line?

3 + 5 + 6 = 14

Correct answer: 3 + 2 + 1 = 6

3 + 5 + 1 = 6

Exit quiz

Download exit quiz

6 Questions

Q1.

We can add numbers in any order. We say that addition is __________

equal

subtraction

Correct answer: commutative

Q2.

If you begin by adding the first two addends together, what would your calculation now be?

1 + 8 = 9

Correct answer: 6 + 3 = 9

4 + 5 = 9

Q3.

Match the steps the three different children took to find the number of pieces of fruit altogether.

Correct Answer:First, add together 5 and 2,,which is equal to 7, then add 3

which is equal to 7, then add 3

Correct Answer:First, add together 2 and 3,,which is equal to 5, then add 5

which is equal to 5, then add 5

Correct Answer:First, add together 5 and 3,,which is equal to 8, then add 2

which is equal to 8, then add 2

Q4.

Laura has been adding three addends by combining different pairs. Match each starting expression to her new equation.

Correct Answer:3 + 4 + 2 ,7 + 2 = 9

7 + 2 = 9

Correct Answer:6 + 2 + 1 ,6 + 3 = 9

6 + 3 = 9

Correct Answer:2 + 3 + 5 ,5 + 5 = 10

5 + 5 = 10

Q5.

Which equations represent the part-part-whole model?

Correct answer: 1 + 3 + 5 = 9

Correct answer: 9 = 3 + 1 + 5

9 + 3 + 1 = 5

Correct answer: 5 + 3 + 1 = 9

Q6.

Which expressions are equal?

Correct Answer:2 + 3 + 4 ,4 + 3 + 2

4 + 3 + 2

Correct Answer:1 + 4 + 3,4 + 1 + 3

4 + 1 + 3

Correct Answer:3 + 4 + 3,3 + 3 + 4

3 + 3 + 4

Additional material

Download additional material