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Math - Introduction to the Decimal System
LevelPrimary
Age4 - 5
Card Layout
Materialslarge number cards
tray
2 small bowls for unit beads

This activity teaches the child the association of the numerals and the quantities.

Presentations

Presentation 1

1. Lay out the material as shown.
The teacher should sit where she can reach the number cards and the small tray with the mat. (The mat with the beads can be placed farther away if there is sufficient room.)
2. The teacher picks on card (20 in this case) and places it on the child's tray.
3. The child takes the tray to the mat with the beads and retrieves the quantity.
4. The child should then return the tray to the mat. Place the number card at the top of the mat.
5. Count out the ten bars as you place them on the mat. "One ten, two tens." Be sure to place the ten bars under the tens place of the card. Point to the number card, "This says two tens." Point to the ten bars, "This is two tens."
6. Return the card and the beads to their places in the layouts.
7. Repeat this process with a quantity of units:
8. or hundreds:
9. or thousands. Continue as long as the child shows interest.

Presentation 2

1. Give the child cards for two adjacent place values (tens and units, hundreds and tens, or thousands and hundreds).
Have the child retrieve the quantity of beads.
Have the child bring the quantity to the teacher's mat. Count out the beads and place as shown.
2. Show the child how to combine the number cards by stacking them and sliding them so they meet on the right edges.
3. Give the child cards for two non-adjacent place values (hundreds and units, thousands and tens, or thousands and units).
Have the child retrieve the quantity of beads.
Have the child bring the quantity to the teacher's mat. Count out the beads and place as shown.
4. Stack and slide the cards to reveal the combined number.
5. Point to the zeros: "See, there are no hundreds or units."

Variations and Extensions

• place value worksheets with base ten blocks at Math-Aids.com
• Get a quantity of beads and ask the child to find the number card that says how much you have.
• Have the child fetch quantities with three, then four place value cards.