# The Exchange Game

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The Exchange Game
Math - Introduction to the Decimal System
LevelPrimary
Age4 - 5
PrerequisitesThe Exchange Tray
tray

This activity shows the child that when quantities are organized it is much easier to see how much you have.
It also gives the child practice in exchanging.

## Presentation

1. Lay out a rug with two small bowls for counting unit beads
2. Take the child to the bead cabinet and start filling a tray with a random amount of units, tens, hundreds, and thousands.
Take the tray to the mat. "What a mess! I wonder how many beads we have here."
3. Sort the beads into piles by place value.
4. Start counting the units.
5. When you get to 10 units, have the child exchange them for 1 ten bar.
Place this ten bar with the others.
6. Count the remaining units (if there are any).
Exchange for ten bars if needed unit until there are fewer the ten units left.
7. Start counting the tens.
8. When you get to ten have the child exchange these for 1 hundred square.
Place this with the other hundred squares. Exchange again if needed until you have fewer than 10 ten bars.
9. Start counting the hundreds.
10. When you get to 10 hundreds, have the child exchange them for 1 thousand cube.
Place this thousand cube with the others. Exchange again if needed until you have fewer than 10 hundreds.
11. Allow the child to see how easy it is to tell how much you have after exchanging.

## Points of Interest

• having a chaotic mixed-up amount of beads at the beginning

## Control of Error

There will be fewer than 10 in each pile