Bead Bars Multiplication: By Ten
- Box of colored bead bars 1-10
- Chart I
- Small white strips of pape
- Black pen
- The child is invited to take 10 bars of any color he wants.
- Lay them in a column, skip counting as you go.
- When he is finished and has found the total, lay out the corresponding number of 10 bars vertically in a row beneath the column (note the resulting rectangles should be congruent).
- The number we took was 4 (place a label for 4 beneath the row of beads), 10 times. The result was 40.
- Directress asks the child; "How do we write 40? The 4 will now indicate tens, and we put a zero for the units". Place a 0 label next to the 4 to make 40.
- Repeat this with other numbers until the child realizes by himself that when you multiply a number by 10, the product will be the multiplicand with a zero tacked on in the units place.
Control Of Error
Points Of Interest
- To help the child with the memorization of multiplication.
- To help the child with the independent realization of the fact stated previously: n x 10 = n0.