On 6/25/09, Elementary Teacher wrote:
> I teach elementary school, and I have always thought
> multiplication was just repeated addition. Can you explain
> to me why it's not?

Thinking of multiplication as repeated addition is a fine way
to start, but, unfortunately, for many students it ends there.

From an earlier post by someone else:
"[...] multiplication is not the same as repeated addition.
[...] One may engage in repeated addition to evaluate the
result of multiplying, but envisioning adding some amount
repeatedly cannot support conceptualizations of
multiplication. [...] Generally, most students do not see
proportionality in multiplication. "

If you want a student to find the area of a rectangle that's 5
squares across and 6 squares tall, you don't really want them
doing 5+5+5+5+5+5 or 6+6+6+6+6. You want them doing 5x6.

The reason for memorizing the multiplication table (through
10's or 12's) is that it gets this thinking solidified. If a
student always does multiplication by repeated addition, then
there's a lot of concepts that will be too computationally
difficult to understand, and the student will be forever
hindered by this.

That's my take on it, anyway. I'd love to hear others'.

Pragmatic

Share This Post | Report This Post

Next Post >>

Posts on this thread, including this one