I plan on doing something for Pi day on March 14th, by the way. Another hobby of mine is Mathematics. I did this recently, and I plan on doing it in a park on March 14th with a whiteboard.
Basically, the more sides a regular polygon has, and the smaller the angle connecting each side, the closer you get to pi if you do this equation where r equals 1 and n is the number of sides.
(n/2) r^2 sin (360/n)
Jared

Basically, the more sides a regular polygon has, and the smaller the angle connecting each side, the closer you get to pi if you do this equation where r equals 1 and n is the number of sides.
(n/2) r^2 sin (360/n)
Jared