Addition & subtraction

Put the groups together

See addition as joining two amounts.

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5 practice questions · Optional read aloud · Thinking pad

Let’s understand the idea.

  1. Start with two groups. Each group tells an amount.
  2. Move the groups together without losing or adding a counter.
  3. The plus sign shows joining. The total tells how many are in the whole group.

Try it. Change it. Explain it.

Open the lesson to use its pictures and controls. In How it works, connect the picture to the idea. In Play & discover, change the quantities and notice what stays the same. In Your turn, answer questions and use the explanation to check your reasoning.

You can ask for help, draw on the thinking pad, or listen to the question and answer options. Progress distinguishes independent work from work completed with help.

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Curriculum connection

Kindergarten · K.OA · US Common Core

K.OA.A.1

This lesson is mapped to these standards. A completed activity is practice evidence, not a claim of mastery. Content is checked against the linked official standards and its mathematical models are tested.

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