Math

One minute math and quick memorization usually doesn’t work for VSL students. A good way to introduce math facts is to make a graph chart and then explain the BIG picture by breaking it down into what they already know (especially for multiplication). Take a piece of paper and lay it diagonally across the grid to expose the upper-right half of the grid. Explain that they really only need to know this many as the other half is a mirror to it. Then go through the ones that they already know (can highlight them), such as the 1’s, 2’s, 5’s, 10’s, 11’s. This will make the amount that they need to LEARN/MEMORIZE even smaller.

You can teach them the 9’s by using the finger-method (putting down the number you’re multiplying 9 by and them counting the fingers on each side) or show them the pattern: taking one less than the number you are multiplying and putting it into the tens place, then the number in the one’s place will make the 2 numbers add up to 9. The numbers also mirror each other if you write them into a >-shape-beginning with 09 and ending with 90. Students can be taught to sing the multiples of 3 to the tune of “jingle-bells”.

4’s can be introduced by teaching students to double the 2’s.

11’s can be introduced by teaching students to split the digits: such as 11 x 12.

a) split 12 1 2

b) add the 2 numbers 1 3 2

This will work for any number greater than 10, even with carrying. 11 x 68

a) split 68 6 8

b) add the 2 numbers 6 (1)4 8

c) carry the 1 and the answer is 748.

12’s can be introduced as another pattern (which VSLs love!) The ten’s number increases by one each time and the one’s number increases by 2 each time. Line them up to show the pattern to your students:

108

Make sure students carry the one when the number changes to a 10.

There are a few left that need to be memorized: 8 x 8 can be memorized with the saying: 8 times 8 went to the store to buy a Nintendo 64. You can also have them draw out the ones that they have difficulty memorizing, such as a pot with flowers and petals, dolphins with bubbles, etc…

Multi-digit multiplication can be taught in a lattice style. It is best to use larger graph paper for this. Suppose the problem is 243 x 68.

a) Create a grid on the graph paper that has 3 squares across and 2 squares down (3x2 grid).

b) Write the numbers 243 across the top (each in it’s own box). Write 68 down (each in it’s own box)

c) Next, divide each square diagonally from the top right to the bottom left.

d) Multiply the top left number by the top right number and write it into the split. i.e. 2 x 6 equals 1/2. 4 x 6 equals 2/4. Etc.. Do the same for the bottom numbers taking the top right number times the bottom left number until your grid is full.

e) Extend the diagonal lines from the grids downward (right-left) so that they fall below the problem.

f) Add the columns. Your answer to 243x68 should be 16524. Make sure they carry right-to-left as they would in a normal problem.

If you are concerned about the time to draw out the graphs, you can offer the graph paper or have the graphs pre-drawn. The important issue is the understanding of the concept, so pre-drawn graphs will not give students any extra advantage- it just levels the playing field.

There are many great manipulatives available, for all ages through Cuisenaire (http://www.etacuisenaire.com) or from Borenson and Associates (http://www.borenson.com)