Topic 6 of 8

Teen numbers as ten and some ones

Step 2 · Numbers to 100 topics

The numbers 11 to 19 are one ten and some more ones. Build them, write them, and take them apart.

A ten and some ones

Each teen number is a full ten and some extra ones. 14 is ten and 4 more. 19 is ten and 9 more.

One full ten frame and 4 more: 14.

The written number tells you this. In 14, the 1 stands for one ten and the 4 stands for 4 ones.

Building teen numbers

To build a teen number, fill a ten frame, then put the extra ones beside it. Or bundle ten sticks with a band and put the extra sticks next to the bundle.

A ten-stick and 6 ones make 16. A ten-stick and 2 ones make 12.

Writing it as adding: 10 + 6 = 16 and 10 + 2 = 12.

Taking teen numbers apart

To take a teen number apart, find the ten and count what is left. 17 is 10 and 7, so 17 = 10 + 7.

Example: Finding the ones

How many ones are there in 18, beyond the ten?

18 is a ten and some more.
After the ten, count on to 18: eleven, twelve… eighteen is 8 more.

Answer8 ones

Try it yourself

Work each one on paper first, then open the answer to check.

10 + 3
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13.
15 is ten and how many more?
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5.
Write 10 + 9 as one number.
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19.
A full ten frame and 7 more counters. How many counters?
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17.
Write 12 as ten and some ones.
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10 + 2.