Read It, Write It, Build It!

Lesson Plan - Get It!

Audio:

How Numbers Work

All numbers are made from ten digits:

0, 1, 2, 3, 4, 5, 6, 7, 8, 9

Each digit has a place. The place tells what the digit means.

Start from the right.

Ones place: counts single things

Tens place: counts groups of 10

Hundreds place: counts groups of 100

Each place is ten times bigger than the one before it.

Example: Look at the number 345.

So, 345 means 300 + 40 + 5.

This way of writing a number is called expanded form.

Why Zeros Matter

Zero is important. It shows when there is nothing in a place.

Look at 809.

• 8 hundreds
• 0 tens
• 9 ones

The zero keeps the 8 in the hundreds place.

Writing Numbers in Words

Numbers can be written in two ways.

With digits: 345

With words: three hundred forty-five

Here is how to write numbers in words.

Step 1: Say the hundreds

Step 2: Say the tens and ones

Example: 345 — three hundred forty-five

Helpful Rules

Do not use the word “and” in whole numbers

Use a hyphen for numbers like twenty-three or sixty-seven

Examples

• 23 — twenty-three
• 90 — ninety
• 111 — one hundred eleven

Writing Numbers With Digits

Now go the other way.

Example: Eight hundred nine

Break it apart.

Put it together: 809

Why This Matters

Numbers are everywhere.

• In games
• With money
• When telling time
• When counting things

Knowing how to read and write numbers helps you understand what you see every day.

You learned how numbers are built, how to write them in words and digits, and how to break them into parts using expanded form.

Now it’s time to practice. Move on to the Got It? section and try it yourself.