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The teen numbers

Understand that the teen numbers (11–19) are composed of ten ones and some further ones (early place value)

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What a learner can do afterwards

  • Compose 14 as a group of ten and four ones using objects
  • Decompose 17 into 10 + 7 and record as an equation
  • Explain that 13 is 'one ten and three ones'

The lesson

You already know how to count and read numbers past ten. Now look closer at numbers like 11 to 19. Each teen number is one full ten, plus a few more ones.

Tap each block and count out loud.
14 blocks: one full group of ten, and four more ones.
Try it together

Sam has 16 cubes. He puts ten cubes in one tower. Six cubes are left over. Ten and six make sixteen.

Tap each block and count out loud.
Good to know

When you see a teen number, picture one ten already made. Just count the extra ones after it.

Every teen number is one ten and some more ones.

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.

The teen numbers · Mathematics, ages 5 to 7 · LightMySky