Identifying Numbers 1–20 — Grade 1 Mathematics

Numbers are all around us! We use them to count things, measure, and tell the time. In Grade 1 we learn to recognise numbers from 1 to 20, understand what they mean, and say their names. Let's explore the wonderful world of numbers!

What Are Numbers?

A number is a symbol that tells us how many things there are. We write numbers using digits. There are just 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 — and we use them to build every number in the world!

Each number also has a number name — the word we say when we read it aloud. For example, the digit 5 is called five, and the number 12 is called twelve.

💡 Remember: Zero (0) means there is nothing at all — an empty group!

Worked Examples

Example 1 — Number Grid: 1 to 20

Here are the numbers 1 to 20. Say each one out loud as you read it!

Digit	Word	Digit	Word
1	one	11	eleven
2	two	12	twelve
3	three	13	thirteen
4	four	14	fourteen
5	five	15	fifteen
6	six	16	sixteen
7	seven	17	seventeen
8	eight	18	eighteen
9	nine	19	nineteen
10	ten	20	twenty

Example 2 — Real World: Counting Stars

Maya looks up at the sky and counts the stars she can see. Let's count them with her!

⭐⭐⭐⭐⭐ ⭐⭐⭐⭐⭐ ⭐⭐⭐

How many stars? Count them: 1, 2, 3 … 13

13 stars — the number is thirteen

Example 3 — Numbers on a Number Line

A number line shows numbers in order from smallest to biggest. Each number has its own spot!

…

Orange markers show 5, 10, and 20 — special landmark numbers that help us count!

Practice Questions

Try these yourself! Click Show Answer when you are ready to check.

1. Write the number word for 7.

✅ 7 = seven

2. What digit comes after 11?

✅ 12 (twelve) comes after 11.

3. Count the apples: 🍎🍎🍎🍎🍎🍎🍎🍎. Write the number AND the number word.

✅ There are 8 apples — eight.

4. Which number is missing? 15, 16, ___, 18, 19

✅ The missing number is 17 (seventeen).

5. True or False: The number fourteen is written as 41.

✅ False! Fourteen is written as 14, not 41.

Key Points to Remember

We use 10 digits (0–9) to write all numbers.
Every number has a number name — a word we say out loud.
Numbers on a number line go from smallest to biggest, left to right.
10 is a special number — it is two digits put together (1 and 0).
Counting in order helps us find the next or missing number.

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