Question

Dear Mitch,

I like the nine-times table trick you've diagrammed in the past that kids can do with their fingers, but my daughter's teacher won't let them use their fingers.  Any idea on what she can do instead?

 

Yours truly.

 

Julie Anne

 

Answer

Dear Julie Anne,

 

Here are some of the ideas that came to me (in no particular order):

 

For the issue at hand, the 9-times table, a student can simply write the numbers 0-9 vertically, in descending order, like this:

 

9

8

7

6

5

4

3

2

1

0

 

Then, simply begin at the top, and to the right of each of those numbers write the number 0-9 in ascending order, so that you end up with this:

 

90

81

72

63

54

45

36

27

18

09

 

And reading them from bottom to top, you have the nine-times table.

The way to check that you have done the work correctly is by adding the two digits together, and for this group they should always add up to nine.  (For example, 81 becomes 8 + 1, which does in fact equal nine.)

 

Another thought that came to me is this:  you don't have to use your fingers if you can find ten items on your page in a row that you can substitute just as well for fingers.  For example:

If your daughter (or anyone else) were to print on the top of her paper or some 'scrap area for working things out':

 

ILOVEMATH!

 

(AND DO NOT FORGET THE EXCLAMATION MARK, as it is necessary to make it up to 10 characters, like your ten fingers)

 

So, for example, let's say your daughter were asked about 9 x 7; she would count off seven from the left, just as she would have done with her fingers.

 

                                        I L O V E M A T H !

 

 

And she'd have:                       6                        3   =                63

 

Or, if the exclamation point is the kind of thing she might forget, she could practice getting ten 'digits' by printing:

 

WE LOVE MATH

 

Or, very often, with mnemonics, people get lucky: perhaps her first and middle name add up to ten letters or her first and last name; or just her last name or first; or middle initial and last name, or her pet's name... play around enough, and you'll strike BINGO!!

 

Also, the month often works, especially if you add the particular date to it:

 

FEBRUARY 10

 

       Or

 

FEBRUARY 08

 

Or, if all else fails, how about this:

 

I I I I I I I I I I

 

And if she doesn't build up enough confidence by the middle of March or so, I guess three words come to mind:

 

The first is "practice", the second is... uh, I'll get back to that one when I recall it.

But I know the third one!  It's "practice."

 

         !  !  !  !  !  !  !  !  !  !

         0 1 2 3 4  5  6 7 8 9

 

Hope this helps,

Mitch