## Secure the perimeter!

I have found that kids have no problem calculating area and perimeter, provided they can both add and multiply.  The problem is remembering which is which.

In our class, we have a fun way of remembering the difference between the two concepts.  It’s loosely based on my background as a military brat, with a heavy influence from battle scenes in movies.

You know how in movies, the commander will tell his troops to secure the perimeter?  The soldiers race to secure the boundaries so no one can get in.  The classroom version: we spread out, each taking a section of the four walls in our classroom.  Then we remember that perimeter is the boundary of a two dimensional figure.

We “retreat to the main area” when it’s clear that our defenses have been breached.  We hit the decks in the wide-open middle of our classroom.  That way, we remember that the area is the space in the middle.

Vocabulary connection: the word “perimeter” comes from peri, meaning around and meter, meaning measure.  Therefore, perimeter means to measure the distance around the shape.  There are lots of other peri words, but they are mostly scientific.  Most kids should know the word periscope, a device that lets a submariner look around.

Posted in Academics,Math by Corey Green @ May 27, 2011