Difference between revisions of "Dynamic Operations in the Decimal System"
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=== Presentation === | === Presentation === | ||
− | The Change Game: | + | The Change Game: |
#A large quantity is placed on the tray and the child is invited to count it. | #A large quantity is placed on the tray and the child is invited to count it. | ||
− | #Beginning with units, the child counts, but is stopped at 10. Ten units cannot remain loose; they must be exchanged for a ten-bar. | + | #Beginning with units, the child counts, but is stopped at 10. |
− | #The ten beads are exchanged for one ten-bar from the bank. The child continues counting units and placing the correct large numeral cards on the tray. | + | #Ten units cannot remain loose; they must be exchanged for a ten-bar. |
+ | #The ten beads are exchanged for one ten-bar from the bank. | ||
+ | #The child continues counting units and placing the correct large numeral cards on the tray. | ||
#So on to thousands. The cards are arranged and read. | #So on to thousands. The cards are arranged and read. | ||
− | Addition: | + | Addition: |
#The directress reads a problem card. The child performs each command as it is read. | #The directress reads a problem card. The child performs each command as it is read. | ||
− | Subtraction: | + | Subtraction: |
− | #The directress reads a problem card. The child performs each command as it is read. | + | #The directress reads a problem card. The child performs each command as it is read. |
− | #The directress presents the thousand cube and wants to take away 1 unit. | + | #The directress presents the thousand cube and wants to take away 1 unit. |
− | #This may be symbolized with the large and small numeral cards for emphasis. How can this be done? The thousand is changed to 10 hundreds. | + | #This may be symbolized with the large and small numeral cards for emphasis. |
− | #Now can we take away one unit? Not quite yet. Continue on until one unit can be taken away. | + | #How can this be done? The thousand is changed to 10 hundreds. |
+ | #Now can we take away one unit? Not quite yet. Continue on until one unit can be taken away. | ||
#The remaining quantity is counted and represented with small cards. | #The remaining quantity is counted and represented with small cards. | ||
− | Multiplication: | + | Multiplication: |
#As for addition problem cards are prepared. | #As for addition problem cards are prepared. | ||
− | Division: | + | Division: |
#As with static division the child sets about distributing. | #As with static division the child sets about distributing. | ||
− | #When he finds that he doesn't have enough for one hierarchy to go around, he must exchange for a lesser hierarchy. | + | #When he finds that he doesn't have enough for one hierarchy to go around, he must exchange for a lesser hierarchy. |
#When there is a remainder, the corresponding small numeral cards are brought and placed after a small card with the initial r to the right of the result.<br> | #When there is a remainder, the corresponding small numeral cards are brought and placed after a small card with the initial r to the right of the result.<br> | ||
Latest revision as of 04:15, 15 October 2009
Contents
Age
4-7
Materials
- Golden bead material
- Large and small numeral cards
- Symbol cards for the operations
- Problem cards for each operation
Preparation
This is an individual presentation.
Presentation
The Change Game:
- A large quantity is placed on the tray and the child is invited to count it.
- Beginning with units, the child counts, but is stopped at 10.
- Ten units cannot remain loose; they must be exchanged for a ten-bar.
- The ten beads are exchanged for one ten-bar from the bank.
- The child continues counting units and placing the correct large numeral cards on the tray.
- So on to thousands. The cards are arranged and read.
Addition:
- The directress reads a problem card. The child performs each command as it is read.
Subtraction:
- The directress reads a problem card. The child performs each command as it is read.
- The directress presents the thousand cube and wants to take away 1 unit.
- This may be symbolized with the large and small numeral cards for emphasis.
- How can this be done? The thousand is changed to 10 hundreds.
- Now can we take away one unit? Not quite yet. Continue on until one unit can be taken away.
- The remaining quantity is counted and represented with small cards.
Multiplication:
- As for addition problem cards are prepared.
Division:
- As with static division the child sets about distributing.
- When he finds that he doesn't have enough for one hierarchy to go around, he must exchange for a lesser hierarchy.
- When there is a remainder, the corresponding small numeral cards are brought and placed after a small card with the initial r to the right of the result.
Control Of Error
The directress.
Points Of Interest
Purpose
- To exchange equal quantities of different hierarchies
- To reinforce the rule: only 9 units can remain loose
- To reinforce knowledge of the composition of each hierarchy (ten tens=100)
- To realize that one unit revolutionizes a large quantity.
- To further understand the concept of addition, subtraction, multiplication, and division
Variation
Links
Handouts/Attachments