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Fluent adding and subtracting within 10

Fluently add and subtract within 10

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What a learner can do afterwards

  • Answer any addition fact within 10 quickly from memory
  • Answer any subtraction fact within 10 quickly from memory
  • Complete a timed set of within-10 facts with high accuracy

The lesson

You know your number bonds, and you can already add and subtract fast within 5. Now it is time to know every fact within 10 so well that the answer just pops into your head. No counting on fingers, no pausing to think.

Tap each star and count out loud.
7 stars and 3 more stars. Say the fact fast: 7 + 3 = 10.
Try it together

Leo has 10 apples. He gives 4 to his friend. He does not count what is left one by one. He already knows 10 − 4 = 6.

Good to know

When a fact feels slow, use one you already know close by. Since 5 + 5 = 10, then 5 + 4 must be 9, one less. Practice each fact until it feels instant, not counted.

Know every within-10 fact by heart, both adding and subtracting, so the answer comes fast and right.

Watch it

Where it sits

Where this leads

Jobs that lean on this skill. Follow one to see everything it is built on.

Then practise

8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.

Fluent adding and subtracting within 10 · Mathematics, ages 6 to 7 · LightMySky