This grade 1 place value lesson explains tens and ones in one printable page, with definitions, a method and a worked example.
A ten is a bundle of ten ones. Numbers with two digits are made of tens and ones. The left digit shows how many tens there are. The right digit shows how many ones there are. In 47 there are 4 tens and 7 ones. Base-ten blocks help you see this.
Grade 1 Place Value Lesson: key facts
- 10 ones make 1 ten.
- The numbers 11 to 19 are 1 ten and some ones.
- In a two-digit number, the left digit is the tens and the right digit is the ones.
- 10, 20, 30 up to 90 are 1 to 9 tens and 0 ones.
What is a ten?
A ten is a bundle of ten ones. Count ten cubes. Snap them together. Now you have one rod. The rod is one ten.
\(10\) ones \(=\) 1 ten. A ten is a group you can count as one thing.
How do the teen numbers work?
Every number from 11 to 19 has one ten and some extra ones. Look at 13. It has 1 ten and 3 ones. That is \(10 + 3 = 13\).
What do the digits in a two-digit number mean?
A two-digit number has two digits. The left digit tells the tens. The right digit tells the ones. In 43, the 4 means 4 tens and the 3 means 3 ones. So \(43 = 40 + 3\).
| Number | Tens | Ones |
|---|---|---|
| 25 | 2 | 5 |
| 38 | 3 | 8 |
| 71 | 7 | 1 |
What are 10, 20, 30, up to 90?
These numbers have zero ones. Only tens are in them. 30 is 3 tens and 0 ones. The words go: ten, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety.
Why do we count in tens?
Counting 47 cubes one by one takes a long time. It is faster to make bundles. First count by tens: 10, 20, 30, 40. Then count the loose ones: 41, 42, 43, 44, 45, 46, 47. Bundles also make big numbers easy to see. A number with more tens is a bigger number.
How do you read base-ten blocks?
- Count the rods. Each rod is one ten.
- Count the loose cubes. Each cube is one one.
- Write the tens digit first. Then write the ones digit.
Example: 5 rods and 6 cubes. The tens digit is 5. The ones digit is 6. The number is 56. Now try the other way. To show 27, grab 2 rods and 7 cubes.
Tens and Ones: frequently asked questions
What is a ten in first grade math?
A ten is a group of 10 ones. You can bundle 10 cubes into one rod and count it as 1 ten.
How many ones are in 1 ten?
There are 10 ones in 1 ten. So 2 tens are 20 ones, but we write them as the number 20.
What does the 0 in 30 mean?
The 0 means there are no ones. The number 30 is 3 tens and 0 ones.
How do I write 4 tens and 7 ones as a number?
Write the tens digit first and the ones digit next. 4 tens and 7 ones is the number 47.
Why is 14 one ten and four ones?
The 1 in 14 stands for 1 ten, which is 10. The 4 stands for 4 ones. So 10 and 4 more is 14.
How to use this grade 1 place value lesson
Use this grade 1 place value lesson before the worksheet, then check what you learned with the quiz.
See every chapter on the Grade 1 math page.
