X Tables
Number Sense

Counting in tens

Use fingers, bundles and ten frames to count by tens.

Quick answer

Counting in tens means grouping objects into sets of ten and counting how many groups there are, so you can quickly count large numbers.

Learning outcome

By the end of this page, you will be able to count large numbers by grouping them into tens and quickly tell how many tens there are. Success signs:
  • You can group 20, 30, 40, 50, 60, 70, 80, 90, 100 objects into tens
  • You can say how many tens are in a number like 60 or 90
  • You can count by tens using your fingers, counters, or ten frames
  • You can use counting in tens to solve simple problems

Why this matters

Counting in tens helps you quickly count big groups of things. It's useful for counting money, measuring, cooking, and even for games and sports. When you know how to count in tens, you can solve problems faster and understand bigger numbers better. In school, counting in tens helps you learn how numbers work and makes it easier to add and subtract larger numbers later. It also helps you understand how our number system works – each place in a number means ten times more than the one before it.

How it works

Counting in tens means you make groups of ten and count how many groups you have. Step 1: Look at a pile of objects. Count how many there are in each group of ten. Step 2: Make sure each group has exactly ten objects. Step 3: Count how many groups of ten there are. Step 4: Say how many tens there are. For example, if you have 30 pencils, you can make 3 groups of 10 pencils each. So there are 3 tens.

Examples you can see

Let's imagine you have a big bag of marbles. You want to count them quickly. Here’s how you do it: Example 1: You have 40 marbles.
  • Make 4 groups of 10 marbles each.
  • Count the groups: 1 group, 2 groups, 3 groups, 4 groups.
  • So there are 4 tens in 40 marbles.
Example 2: You have 70 blocks.
  • Make 7 groups of 10 blocks each.
  • Count the groups: 1 group, 2 groups, 3 groups, 4 groups, 5 groups, 6 groups, 7 groups.
  • So there are 7 tens in 70 blocks.
Example 3: You have 100 stickers.
  • Make 10 groups of 10 stickers each.
  • Count the groups: 1 group, 2 groups, 3 groups, 4 groups, 5 groups, 6 groups, 7 groups, 8 groups, 9 groups, 10 groups.
  • So there are 10 tens in 100 stickers.

Try it as a mini adventure

Adventure: The Treasure Hunt You are going on a treasure hunt with your friends. You find a chest full of coins. You want to count how many coins there are without getting tired. Step 1: Collect the coins into groups of ten. Step 2: Put each group of ten coins in a small box. Step 3: Count how many boxes you have. Step 4: That number is how many tens there are in your total number of coins. Step 5: If you have 6 boxes of coins, that means you have 6 tens, or 60 coins. Try this with your toys, or with a pile of pencils, or even with your snacks!

Common mistakes

  • Mistake: Counting each coin individually instead of grouping them into tens.
    Why it happens: It's easier to count one by one when you're not used to grouping.
    Fix: Try making groups of ten first, then count the groups.
  • Mistake: Thinking that 20 is 2 tens, but 30 is 3 tens, and so on, but forgetting that 100 is 10 tens.
    Why it happens: It's hard to imagine 10 groups of 10.
    Fix: Use objects like blocks or counters to make 10 groups and see that 10 groups of 10 = 100.
  • Mistake: Saying that 50 is 5 tens, but 60 is 6 tens, and then getting confused with 100.
    Why it happens: The pattern isn't obvious at first.
    Fix: Practice counting by tens using your fingers or counters.
  • Mistake: Forgetting that 0 tens is 0.
    Why it happens: Zero can be confusing.
    Fix: Remember that if you have no groups of ten, then you have 0 tens, which is 0.

Parent and carer guide

Counting in tens helps children understand how numbers work. As a parent or carer, you can help by:
  • Using everyday items like buttons, coins, or pasta to make groups of ten.
  • Counting in tens together when you're out shopping or walking.
  • Using a ten frame or counters to show how groups of ten look.
  • Practising counting in tens using your fingers or a number line.
  • Encouraging your child to explain how many tens they see in a number.
Remember: It's okay if your child makes mistakes. Counting in tens takes practice. Keep it fun and keep trying!

Practice questions

  1. How many tens are in 30?
  2. How many tens are in 50?
  3. How many tens are in 80?
  4. How many tens are in 100?
  5. How many tens are in 40?
  6. How many tens are in 70?
  7. How many tens are in 20?
  8. How many tens are in 90?
  9. How many tens are in 60?
  10. How many tens are in 10?
Answers:
  1. 3 tens
  2. 5 tens
  3. 8 tens
  4. 10 tens
  5. 4 tens
  6. 7 tens
  7. 2 tens
  8. 9 tens
  9. 6 tens
  10. 1 ten

FAQ

What does it mean to count in tens?

Counting in tens means making groups of ten and counting how many groups there are.

Why is counting in tens helpful?

It helps you count big numbers quickly and understand how numbers are built up from tens.

Can I use my fingers to count in tens?

Yes! You can count by tens using your fingers or counters.

How can I practice counting in tens?

You can practice by grouping objects into tens, using a ten frame, or counting in tens with your family.

What comes after 100 when counting in tens?

After 100 comes 110, 120, 130, and so on.