Understand that 10 can be thought of as a bundle of ten ones, called a 'ten'
You already know the teen numbers, like 11, 12, and 13. Every teen number starts with one full ten hiding inside it. Today you will learn what that ten really is: it is ten single ones, bundled together and given a new name.
Ravi lines up his 10 cubes in a straight row and snaps them together. Now instead of 10 loose cubes, he has one long rod. That rod is called a ten.
Whenever you count out exactly 10 ones, you can trade them in for a tens block. No cubes left over, and none missing.
That is why the number 10 is written with a 1 and a 0. The 1 stands for 1 ten, and the 0 means there are no extra loose ones left.
Ten ones bundled together make one ten, and that is why 10 has a 1 in the tens spot and a 0 in the ones spot.
You have counted teen numbers like 11, 12 and 13. Every one of them hides one full ten inside. Today you get to see what that ten is made of. Ravi tips his cubes onto the table to build one.
How many loose ones does Ravi need to snap together to make one ten?
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