"If you read a child a math book" (with apologies to Laura Numeroff)

If you read a child a math book...(like Mummy Math)

he will want to make Platonic Solids models...

with toothpicks and gumdrops...

like tetrahedrons...

and octahedrons...

and that might make him a little confused...

but he'll keep working at it and he will get it...

and then he might want make polyhedra models...

and that will remind him of one time we counted shape faces and he'll want to do it again and that will make him want to count the vertices and edges...

..and that will lead the oldest child to remember when we did this before and that will lead to Euler's Polyhedron Formula,

V-E+F=2...

and that will lead to counting in positive and negative numbers...and then he'll want you to read another.

Living math books with these geometric concepts:

• Mummy Math by Cindy Neuschwander (grades 1-4)
• Sir Cumference and the Sword in the Cone by Cindy Neuschwander (Grades 3-5)
• Mathematicians Are People, Too: Stories From the Lives of Great Mathematicians, Luetta Reimer (ages 8 and up)
• Leonhard Euler and the Bernoullis: Mathematicians from Basel, M. B. W. Tent (6th grade and up)

What is a polygon? 

The first time we visited the topic of polygons, we used some paper polygons. The we made a chart, counting the edges and vertices with a marker. The older students could plug in Euler's formula. While talking about it we discovered that the same formula can be applied to 2-dimensional figures with a constant of 1 instead of 2. Makes one think, huh?

This time we used toothpicks and gumdrops, which we have done before. Toothpicks and gumdrops are good to work with to make regular polygon because the equal sized toothpicks make them automatically have all their sides the same length. This time when we counted the edges and vertices, they were easy to count because the edges are the sides, denoted by how many toothpicks are used and vertices are where two sides meet up, denoted by how many gumdrops are used. This time, because we wanted to look closely at the Platonic solids, they measured the angles with a protractor and (with a little adjusting) correctly determined that three of the five Platonic Solids are made out of equalateral triangles. I thought it was interesting that Tiffini at Child's Play, when she did this lesson, also brought the children's attention to Polyhedral Dice and their shapes, which made counting the sides even easier as that is how the dice are named. We use those dice all the time for our math games.