Numbers live on a number line. It is like a road with a number at every step. Today we explore the numbers from 0 to 20.
The number line
0 – 1 – 2 – 3 – 4 – 5 – 6 – 7 – 8 – 9 – 10 – 11 – 12 – 13 – 14 – 15 – 16 – 17 – 18 – 19 – 20
As we move to the right, the numbers get bigger. As we move to the left, they get smaller.
Before, after and between
- The number before 14 is 13.
- The number after 14 is 15.
- The number between 16 and 18 is 17.
Teen numbers: ten and some more
The numbers 11 to 19 are made of ten and some more.
| Number | Ten and … | Word |
|---|---|---|
| 11 | 10 and 1 | eleven |
| 12 | 10 and 2 | twelve |
| 13 | 10 and 3 | thirteen |
| 14 | 10 and 4 | fourteen |
| 15 | 10 and 5 | fifteen |
| 16 | 10 and 6 | sixteen |
| 17 | 10 and 7 | seventeen |
| 18 | 10 and 8 | eighteen |
| 19 | 10 and 9 | nineteen |
| 20 | 10 and 10 | twenty |
TRY ITThe number line game
Use the number line. Tap the right answer.
Let’s practise
Try each one. Then tap Show answer to check.
1. What number comes just before 11?
Show answer
10.
2. What number is between 18 and 20?
Show answer
19.
3. Fill the gap: 12, 13, ___, 15
Show answer
14.
4. Fill the gaps: 16, ___, 18, ___, 20
Show answer
17 and 19.
5. Ten and 6 more makes ___.
Show answer
16.
6. 17 is ten and ___ more.
Show answer
7.
7. Count down: 20, 19, 18, ___, ___
Show answer
17, 16.
Quick check
1. Which is bigger: 13 or 19?
Show answer
19. It is further to the right on the number line.
2. Put these in order from smallest: 15, 11, 20, 8
Show answer
8, 11, 15, 20.
3. What is ten and 10 more?
Show answer
20 (twenty).
Maths words
Say these words with a grown-up. Can you use each one in a sentence?
number line · before · after · between · teen numbers · ten and … more · order
Try it at home
- Make a number line with chalk on the step or with paper on the floor. Hop from number to number.
- Ask: “I am thinking of the number after 15. What is it?” Then swap.
- Use 10 bottle caps and some more to show teen numbers, for example 10 and 4 more is 14.
For parents and teachers
After this lesson, your child should be able to:
- find the number before, after or between numbers up to 20
- fill in missing numbers on a number line
- count up from 0 and down from 20
- order numbers to 20 from smallest to largest
- describe numbers 11 to 19 as ten and some more
- match numerals and number names
Seeing teen numbers as “ten and some more” is the first step towards place value. Ten-frames (egg boxes cut to 10 cups) are great for this.
Previous: How Many? Counting to 20
Next: More, Less and About How Many?
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