Techniques for Mental Arithmetic

There are many tricks to teach children multiplication facts in mathematics. Some tricks that I used to use in my classroom are listed here. If you know of some that I may have missed, drop into the forum and let everyone know. I'll add them to this list as I see them.

The 9 Times Quickie

Hold your hands in front of you with your fingers spread out.
For 9 X 3 bend your third finger down. (9 X 4 would be the fourth finger etc.)
You have 2 fingers in front of the bent finger and 7 after the bent finger
Thus the answer must be 27
This technique works for the 9 times tables up to 10.
The 4 Times Quickie

If you know how to double a number, this one is easy.
Simply, double a number and then double it again!
The 11 Times Rule #1

Take any number to 10 and multiply it by 11.
Multiply 11 by 3 to get 33, multiply 11 by 4 to get 44. Each number to 10 is just duplicated.
The 11 Times Rule #2

Use this strategy for two digit numbers only.
Multiply 11 by 18. Jot down 1 and 8 with a space between it. 1 --8.
Add the 8 and the 1 and put that number in the middle: 198
Deck 'Em!

Use a deck of playing cards for a game of Multiplication War.
Initially, children may need the grid (below) to become quick at the answers.
Flip over the cards as though you are playing Snap.
The first one to say the fact based on the cards turned over (a four and a five = Say "20") gets the cards.
The person to get all of the cards wins!
Children learn their facts much more quickly when playing this game on a regular basis.
Seeing the Patterns

Use a multiplication grid or let your students/children create one.
Look carefully at all of the patterns, especially when the numbers correspond with the facts e.g., 7X8 and 8X7 = 56
Let students/children practice the 'fast adding' which is what multiplication is.
When students can count by 3s, 4s, 5s 6s, etc. they will automatically know their multiplication tables.