Write Numbers 0 To 20 — CCSS.K.CC.3: Write numbers from 0 to 20. Represent a number of objects with a written numeral 0-20 (with 0 representing a count of no objects). - Kindergarten Math

SECTION 1

Where Did Numbers Come From?

A long, long time ago, people did not have numbers. If a farmer wanted to know how many sheep she had, she would put one stone in a pile for each sheep. That was a lot of stones! People needed a better way to keep track of how many things they had. So over many years, people made up symbols — the numerals we use today — to stand for amounts.

30,000 BC • Tally Marks

Early people scratched lines on bones and cave walls to count things like animals and days.

3000 BC • Egyptian Numbers

Ancient Egyptians drew little pictures to stand for numbers. A stick meant 1, and a heel bone meant 10!

500 AD • The Number Zero Is Born

People in India invented the number 0. Before that, there was no way to write 'nothing.' This was a very big idea!

1200 AD • Our Numbers Spread Around the World

The numerals 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 traveled from India to Arabia and then to Europe. We still use these same ten digits today!

Today, you get to learn those same amazing symbols. When you write the numbers 0 to 20, you are using a system that people worked on for thousands of years. How cool is that? The big question is: How do we write a numeral that tells exactly how many objects we see?

SECTION 2

Big Ideas About Writing Numbers

Before we start writing, let's learn some important ideas. A numeral is a written symbol that stands for a number. For example, the numeral "5" stands for five things. A digit is one of the ten symbols we use: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Every number is built from these ten digits!

Zero Means None

The number 0 means there are no objects at all. If you have 0 apples, your hands are empty!

One-Digit Numbers (0–9)

The numbers 0 through 9 each use just one digit. You only need one symbol to write them.

Two-Digit Numbers (10–20)

The numbers 10 through 20 use two digits side by side. The first digit tells the tens and the second digit tells the ones.

Count, Then Write

To write the right numeral, first count the objects carefully. Touch each one as you count. Then write the numeral that matches your count.

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KEY TAKEAWAY

Think of numerals like name tags for amounts. Just like your name tag tells people who you are, a numeral tells people how many objects there are. If there are no objects, the name tag says 0. If there are 14 crayons, the name tag says 14!

SECTION 3

See the Numbers!

Let's look at a picture that shows how objects match up with numerals. Each group of stars below has a numeral next to it. Notice how the numeral always tells you the exact number of stars in the group.

Each box shows a group of stars and the numeral that tells how many. Notice the box for 0 has no stars at all!

Look at the boxes in the picture above. The box for 0 has no stars inside. That's because 0 means "none." The box for 5 has exactly five stars, and the numeral 5 is written below. When we get to bigger numbers like 10, 15, and 20, we need two digits. The numeral 10 uses a 1 and a 0 together. The 1 means one group of ten, and the 0 means zero extra ones.

SECTION 4

How Tens and Ones Build Numbers

Numbers 0 through 9 are easy — they each have just one digit. But what happens when we get past 9? We start using tens and ones! Think of it this way. When you have ten things, you can bundle them into one group of ten. The first digit tells you how many tens, and the second digit tells you how many extra ones.

BUILDING A TEEN NUMBER

13 = 1 ten + 3 ones

The digit 1 stands for one group of 10. The digit 3 stands for 3 extra ones. Put them together and you get 13!

THE NUMBER 20

20 = 2 tens + 0 ones

The digit 2 stands for two groups of 10. The digit 0 means there are no extra ones. So 20 is just two tens!

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Special Names for Teen Numbers

The numbers 11 through 19 are called teen numbers. Their names can be tricky! For example, 11 is "eleven" (not "oneteen") and 12 is "twelve" (not "twoteen"). Starting at 13, the names follow a pattern: thir-teen, four-teen, fif-teen, and so on.

Here is a simple way to remember how it works. For any number from 10 to 20, say to yourself: "How many tens? How many ones?" Then write the tens digit first and the ones digit second. That's it!

SECTION 5

All the Numbers from 0 to 20

Let's put every number from 0 to 20 in a chart so you can see them all together. The chart below shows the numeral, the number name, and how many tens and ones are in each number.

The number line at the top shows every number from 0 to 20. The table below breaks down selected numbers into tens and ones.

Numeral	Number Name	Objects
0	zero	(none)
1	one	🍎
2	two	🍎🍎
3	three	🍎🍎🍎
4	four	🍎🍎🍎🍎
5	five	🍎🍎🍎🍎🍎
6	six	🍎🍎🍎🍎🍎🍎
7	seven	🍎🍎🍎🍎🍎🍎🍎
8	eight	🍎🍎🍎🍎🍎🍎🍎🍎
9	nine	🍎🍎🍎🍎🍎🍎🍎🍎🍎
10	ten	🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎

Numbers 0 through 10 with apple objects

SECTION 6

Let's Count and Write Together

Imagine you look at a picture and see a bunch of butterflies. How do you figure out which numeral to write? Follow these easy steps!

How Many Butterflies? 🦋🦋🦋🦋🦋🦋🦋🦋🦋🦋🦋🦋🦋🦋

1
Step 1 — Touch and Count Each One

Point to each butterfly and say a number out loud. Start with 1 and keep going. Do not skip any butterfly! 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14.

You counted 14 butterflies.
2
Step 2 — Ask: How Many Tens?

14 is more than 9, so it has some tens in it. Ten of those butterflies make one group of ten. So there is 1 ten.

Tens digit = 1
3
Step 3 — Ask: How Many Extra Ones?

After taking away the group of 10, how many are left over? 14 − 10 = 4. So there are 4 ones.

Ones digit = 4
4
Step 4 — Write the Numeral

Put the tens digit and the ones digit together. Write the 1 first, then the 4 right next to it.

The numeral is 14!

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KEY TAKEAWAY

Writing a numeral is like taking a photo of how many things you see. First you count carefully, then you write the matching numeral. That numeral is like a snapshot that tells anyone exactly how many objects were there!

SECTION 7

Common Mistakes and Helpful Tips

Writing numbers is a skill, and skills take practice! Here are some things to watch out for, and some tips that will help you get better.

Common Mistake	Why It Happens	Helpful Tip
Writing numbers backwards (like ε instead of 3)	Your hand is still learning how to form shapes.	Practice tracing the number first. Say the direction out loud: "Curve right, curve right."
Skipping a number when counting	You moved too fast and lost track.	Touch each object as you count. Move them to a new pile after you count them.
Writing 12 as 21 (swapping digits)	You mixed up the tens place and ones place.	Always write the tens digit first (on the left). The ones digit goes second (on the right).
Forgetting that 0 is a number	It feels strange to write a number for nothing.	Remember: 0 is the numeral that means 'no objects.' It is an important number!

Watch out for these common mistakes!

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REMEMBER THIS

Mistakes are a normal part of learning! Even grown-ups had to practice writing numbers when they were your age. The more you practice writing each numeral, the easier it will feel. Try writing numbers in sand, on a whiteboard, or even in the air with your finger!

SECTION 8

Getting Ready for Bigger Numbers

Right now you are learning numbers from 0 to 20. But guess what? Numbers keep going — they never stop! Once you feel great about writing 0 to 20, you'll be ready to write even bigger numbers like 50 or 100. The same ideas you learned today — tens and ones — will help you with those bigger numbers too.

What You Know Now	What Comes Next
Write numerals 0 to 20	Write numerals all the way to 100 and beyond
Count objects up to 20	Count larger groups and skip count by 2s, 5s, and 10s
Know that 0 means no objects	Use 0 as a placeholder in numbers like 30, 40, 50
Break numbers into tens and ones	Start adding and subtracting with tens and ones

From 0–20 to bigger math adventures!

In first grade, you will learn to count and write numbers up to 120. You will also start to compare numbers to see which one is bigger. Everything you are learning right now is building a strong base. Think of it like building blocks — the numbers 0 to 20 are the bottom row of your tower. Without them, you can't stack anything on top!

SECTION 9

Practice Problems

Now it's your turn! Try these five problems. Start with the easy ones and work your way up. You can do it!

Question 1: CONCEPTUAL

You look at an empty plate. There are no cookies on it. What numeral do you write to show how many cookies are on the plate?

Show answer

You write the numeral 0. The number 0 means there are no objects. Even though the plate is empty, we still have a numeral for that amount. Zero is an important number because it tells us "none."

Question 2: BASIC CALCULATION

Count these hearts: ❤️❤️❤️❤️❤️❤️❤️. Write the numeral for how many hearts you see.

Show answer

There are 7 hearts. You can find this by touching each heart and counting: 1, 2, 3, 4, 5, 6, 7. Since 7 is less than 10, you only need one digit. The numeral to write is 7.

Question 3: INTERMEDIATE

You have a bag with 1 ten and 6 ones in it. What numeral should you write to show how many are in the bag? How do you know?

Show answer

The numeral is 16. When you have 1 ten, you write a 1 in the tens place (on the left). When you have 6 ones, you write a 6 in the ones place (on the right). Put them together and you get 16. You can check by counting: 10, 11, 12, 13, 14, 15, 16!

Question 4: APPLIED

Your teacher puts 12 crayons on a table. Three students each take one crayon away. Write the numeral for how many crayons started on the table. Then write the numeral for how many are still on the table.

Show answer

The table started with 12 crayons. Three students each took 1 crayon, so 3 crayons were removed. You can count the ones that are left: start at 12 and count back 3 — that's 11, 10, 9. There are now 9 crayons on the table. Notice that 12 is a two-digit number (1 ten and 2 ones), but 9 is a one-digit number (0 tens and 9 ones).

Question 5: CRITICAL THINKING

Mia says: "The numeral 18 and the numeral 81 show the same amount because they use the same two digits." Is Mia right or wrong? Explain your thinking.

Show answer

Mia is wrong. Even though 18 and 81 use the same digits (1 and 8), the order matters a lot! In 18, the 1 is in the tens place and the 8 is in the ones place, so it means 1 ten + 8 ones = 18. In 81, the 8 is in the tens place and the 1 is in the ones place, so it means 8 tens + 1 one = 81. That is a much bigger number! Where a digit sits changes its value.

SUMMARY

Let's Review What We Learned

Summary

In this lesson, you learned how to write the numbers 0 to 20. You discovered that a numeral is a symbol that stands for an amount, and that we use ten digits (0 through 9) to build every number. The number 0 means no objects at all. Numbers 1 through 9 need only one digit, but numbers 10 through 20 use two digits because they have tens and ones.

The most important skill is to count objects carefully — touching each one — and then write the numeral that matches your count. Remember that the order of digits matters: the left digit tells the tens and the right digit tells the ones. Keep practicing, and soon writing numbers will feel as easy as writing your own name!