IFIT Montessori

6-9.

Materials

• The Horizontal Bead Frame, which lies flat on the table: t is less sensorial in that hierarchic colors and spaces between the classes have been eliminated.
• Box of 4 series of gray cards on which 1-9 is written in black (to serve as multiplier)
• Strips of white paper on which multiplicand will be written.

Preparation

The black lines are drawn on the board beneath the wires; they will indicate where to begin the multiplication when multiplying by units, tens, hundreds or thousands.)

Presentation

1. All of the previous operations can be done with this material, but we will do the most interesting: multiplication with a two-digit multiplier.
2. Directress writes down a problem, 6542 x 36 = and shows the child how to set up this problem.
3. Place a white strip over the zeros and secure it with a rubber band or tape.
4. Write the multiplicand on the strip so that the digits correspond to the correct wires.
5. Find among the gray cards the digits needed to form the multiplier.
6. Place the 6 over the lowest green dot which represents the units, and the 3 over the blue dot for the tens. The beads should be at the top to start.
7. Begin multiplying 2 x 6 = 12, bring down 2 units and 1 ten. 4 x 6 = 24 tens - bring down 4 tens and 2 hundreds and so on.
8. After the multiplicand has been multiplied by the units we can turn over the card '6'.
9. In order to multiply by the 3 tens, 30, we must move the multiplicand to the left one space to let one red zero show. This is just like multiplying the number by 10.
10. The black line indicates that we start with the row of tens.
11. Continue multiplying, making changes as necessary.
12. In the end we read the product and record it.

• Horizontal Golden Bead Frame: Carrying Mentally
• Horizontal Golden Bead Frame: Partial Products