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One-to-one counting

One-to-one correspondence when counting objects: each object is paired with exactly one number name

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What a learner can do afterwards

  • Point to or touch each object exactly once while saying number names
  • Do not skip objects or double-count when counting a set
  • Recognise an error when someone counts an object twice

The lesson

When you count, every thing gets exactly one number. Touch it, say the number, move on.

Tap each star and count out loud.
Touch each star once: 1, 2, 3, 4, 5.
Try it together

Leo counts his apples. He touches each apple one time and says 1, 2, 3, 4. Four apples.

Tap each apple and count out loud.
Good to know

If you touch a thing twice, it gets two numbers, and the count comes out wrong. One touch, one number.

One thing, one number. Never skip, never count twice.

Watch it

Where it sits

Learn first

Nothing; this is a starting point.

This opens up

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.

One-to-one counting · Mathematics, ages 4 to 6 · LightMySky