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Reach Crest Learning

Add and take away · Lesson 12 of 32

Parts make a whole

Read with an adult. Take your time. You can say, point, draw or write your answer.

Let's look together

A group can be split into smaller parts. The whole is all the parts together.

Five blocks can split into two and three. Push them together again: the whole is still five. We did not lose any blocks.

2 and 3 make 5
Look, point and talk with your adult.

Watch how I do it

I cover two of five counters. I can see three. Two hidden and three seen make five altogether.

Your turn

Split six objects into four and a hidden part. How many are hidden?

Have a go before opening the answer.

Let's check together

Two, because four and two make six.

Try it away from the page

Split five blocks in different ways. Draw each split. Include zero and five.

Open your writing and drawing pad

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Adult notes · prerequisites, safety and coverage

Prerequisite: count and compare. Keep the whole unchanged while varying the parts. This prepares bonds and missing numbers.

Use large counters, blocks and paper before symbols. Revisit a lesson until the child can show and explain the idea. Numbers grow from 0–10 to 20, then 100; these pages are not a one-sitting course.

These are teaching introductions, not a claim of mastery. Open the subject's coverage map and limits.