Associated Topics || Dr. Math Home || Search Dr. Math

### Rectangular Arrays to Teach Multiplication

Date: Thu, 10 Nov 1994 12:28:42 -0700 (MST)
From: Anonymous
Subject: multiplication

I'm Glen, hi! I teach fourth grade math. Are rectangular arrays
the best way to teach multiplication?

Date: Thu, 10 Nov 1994 16:10:13 -0500 (EST)
From: Dr. Ken
Subject: Re: multiplication

Hello there, Glen!

Well, I'm not sure we're really your best resource on this question.
I'm happy to tell you my opinion, but I've never been a math teacher
nor have I graduated from college yet, so I may not be of much help
to you.

I think that it's very important for students to see the relationship
between addition and multiplication, i.e. that mulitiplying 7 by 5 is
the same thing as adding seven fives together.  And let them discover
(lead them to it if they need some help) that adding seven fives together
will give you the same result as adding five sevens together.  I mean,
that's a pretty deep result for a fourth-grader.  I know I was excited.

I think that using rectangular arrays is a good way to visualize
mulitiplication, but I also think that kids should be well-grounded
in symbol manipulation, i.e. writing out 7 + 7 + 7 + 7 + 7 and seeing
that it equals 35.  Gaining familiarity with this kind of manipulation
will help them when they start to learn Algebraic manipulation of
variables.

Of course, these are just a couple of ideas.  Perhaps another Math
Doctor will have other ideas.

-Ken "Dr." Math

Associated Topics:
Elementary Multiplication

Search the Dr. Math Library:

 Find items containing (put spaces between keywords):   Click only once for faster results: [ Choose "whole words" when searching for a word like age.] all keywords, in any order at least one, that exact phrase parts of words whole words

Submit your own question to Dr. Math
Math Forum Home || Math Library || Quick Reference || Math Forum Search