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.
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?
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
One-Digit Numbers (0–9)
Two-Digit Numbers (10–20)
Count, Then Write
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.
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.
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.
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!
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.
| 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 | 🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎 |
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!
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! |
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 |
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!
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!
Let's Review What We Learned
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!