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Topic: Polygon Diagonals
Replies: 0

 Judy Ann Brown Posts: 192 Registered: 12/3/04
Polygon Diagonals
Posted: Nov 7, 2000 2:50 PM

When I was teaching 8th grade, I had a fun activity that I did with my
students to help them find the number of diagonals in a polygon.

I made the students the vertices in the polygon.
I started with three students and connected them with black yarn, to
represent the sides of the polygons.

Then we checked to see that we could not make any diagonals.

Next we added a 4th student and another side. Now we could make two
diagonals, this time I used red yarn. We made sure that everyone was
connected to everyone else with either a red or black strand.

Next we added a 5th person and another side. Then of course the
diagonals.

By the time we got up to a decagon we always had a pile of tangled
yarn but a lot of fun and learning had taken place.

I hope that this gives you an idea of how you can introduce this
week's Middle School problem to your students.

Judy