Chapter 1: A Day at the Beach

Imagine warm sand under your feet and a cool wind on your face. Today we are going to the beach , and we will count, count, count!

What we'll do

Count shells, pebbles and crabs we see at the beach.
Make small groups of ten to count quickly.
Read numbers as tens and ones.
Skip count: 10, 20, 30 ...

The big idea

When we have just a few things, we can count them one by one , 1, 2, 3. But what if there are 47 shells on the sand? Counting one by one takes a long time and we lose track.

So here is a clever trick. We pick up the shells and put ten in a small pile. Then ten more in the next pile. Each full pile is one ten. The shells that are left over are called ones.

If we have 4 piles of ten and 7 single shells, that is 4 tens and 7 ones, which we read as forty-seven, or 47.

Counting in groups of ten is faster, and it is how all big numbers are made. Once you can see 10 as one whole bunch, numbers like 30, 50, 80 stop feeling scary.

Let's play!

Pebble piles. Go outside and collect about 35 small pebbles. Make piles of ten. How many full piles? How many pebbles are left? Say the number out loud.

Vallam Kali count. Pretend your toy boats are racing. Line them up in rows of 10. Count: 10, 20, 30 ... How many boats in 3 rows? In 5 rows?

Snap the tens. Take 24 rajma seeds. Snap your fingers each time you make a group of 10. How many snaps? How many extra seeds?

A small story

Meera and her brother went to the beach. Meera picked 23 white shells. Her brother picked 16 brown shells. They put all the shells in a basket. To count them quickly, they made groups of 10. They made 3 full groups of 10 and had 9 shells left over. So in all, they had 39 shells!

Quick check

How many ones are there in 1 ten?
Count in tens: 10, 20, 30, ___, ___.
4 tens and 2 ones make which number?
If you have 28 pebbles, how many full groups of 10 can you make? How many are left?
Which is bigger: 3 tens or 25 ones?

What did we learn?

A group of 10 is called one ten.
Big numbers are made of tens and ones.
Counting in groups is much faster than counting one by one.