Chapter 8: Fun with Numbers

Are you ready for bigger numbers? Today we go all the way to 99! Don't worry , once you know how 10 works, the rest is easy.

What we'll do in this chapter

Count from 21 to 99.
See numbers as tens and ones (like 24 = 2 tens + 4 ones).
Bundle sticks into tens.
Find the number that comes before or after.

The big idea

Big numbers look scary, but they have a simple secret , they are just groups of ten and a few more!

Take 24. That is 2 bundles of ten and 4 single sticks. Two tens and four ones. Easy!

Take 57. That is 5 tens and 7 ones. Try it with matchsticks at home!

When we count, we go in order:

21, 22, 23, 24, 25, 26, 27, 28, 29, 30…

…40, 41, 42… 50… 60… 70… 80… 90… 99!

Every time we reach a new ten (30, 40, 50…), we start counting again with a new digit at the front. The numbers have a rhythm, like a song.

When you have a number like 73, ask yourself: how many tens? (7!) How many ones? (3!) That is the trick.

Let's play!

🪵 Bundle the Sticks

Take 30 matchsticks. Make bundles of 10. How many bundles? (Three!) Now take 8 more single sticks. What is the number? 38!

🔢 What Comes Next?

Say: "47, 48, 49… and now?" Your friend says 50! Then keep going. Try starting from 68. From 89. From 35.

🎁 Number Hopscotch

Draw numbers from 1 to 50 in chalk on the ground (or with cardboard pieces). Hop on every number that ends in 5 , 5, 15, 25, 35, 45. Now hop on the tens , 10, 20, 30, 40, 50!

📋 Tens and Ones Card

Write a number like 62. Now show it as 6 bundles of 10 (draw small lines) and 2 single dots. Try with 27. With 84. With 99.

A small story

Mira's grandfather was 67 years old. She asked, "Dadu, how many tens and how many ones is that?" Grandfather smiled. "6 tens , that is 60. And 7 more. That makes 67!" Mira counted her toys , she had 23. "2 tens and 3 ones, Dadu!" Grandfather hugged her, "Soon I will count my mangoes with you too!"

Quick check

What number is 4 tens and 5 ones?
What comes after 39?
How many tens are in 80?
Write the number before 50.
Count from 95 to 99 out loud.

What did we learn?

Big numbers are made of tens and ones.
We can go all the way up to 99.
Every new ten starts a new little family , twenties, thirties, forties…