It teaches and entertains!
I love combining math and literature. The children get to hear a story and learn math concepts at the same time. Even the topic is fun! Who doesn't like dessert? A real pie or cake to eat after reading the book would be the icing on the cake! (Ha Ha!)
This book can be used to introduce or reinforce the concept of angles. It begins by telling the readers that if they like pie then they also like angles. It explains that every time you cut a piece of pie you are cutting an angle! Cutting a small piece of pie makes a small angle and cutting a large piece of pie makes a larger angle.
The book also relates the size of angles to the length of time using an analog clock which is another great tool to teach angles.
Besides teaching about the angles of a circle this book also introduces angles in a triangle, quadrilateral, pentagon, hexagon, heptagon, and octagon.
Now if you'd like to add measurement to this geometry activity, why not make a pie or cake too!