Identify a missing part when a whole is partitioned into two parts

I can identify a missing part when a whole is partitioned into two parts.

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Year 1

Identify a missing part when a whole is partitioned into two parts

I can identify a missing part when a whole is partitioned into two parts.

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Share activities with pupils

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Lesson details

Key learning points

Numbers can represent measures when a part is missing.
Each of the numbers six to ten can be partitioned into two parts in different ways.
If we know one part we can find the other part.
A bar model can be used to represent the whole number and a missing part.
Knowing about odd and even parts means you know if the missing part is odd or even.

Keywords

Partition - To split a whole up into parts.
Whole - All of something. Complete.
Part - A piece or section of a whole.

Common misconception

Children may confuse the part and the whole, or add the whole and one part to find the missing part.

Encourage the use of the stem sentence ___ is the whole, ___ is a part and ___ is a part, to reinforce what the numbers represent.

Part-part-whole models can continue to be used to record and justify answers to problems. Use part-part-whole models in different orientations and with different numbers of parts for children to use to see objects partitioned in different ways.

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).