Whether you are a mathematician or not, the appropriate way to celebrate Pi Day is eating pie! Or maybe wearing a funny Pi shirt. Pi Day is always March 14, because pi is 3.14. I’m sure there will be an even bigger (and nerdier) celebration in 2015. Just think: 3.14.15!

As I’m *sure* we all remember from high school math class, pi is a mathematical concept that describes the ratio of a circle’s circumference to its diameter. It is also an irrational number and a fraction that never ends, but the short approximation is 3.1415 … and it just keeps on going from there.

See more Pi Day T-Shirts! *Remember if you click on any t-shirt, you can choose the style, color, and size you want, for infants to adults – or choose this design on lots of other gift items too!*

I’ll see you in a funny t-shirt!

Tags: Calculation, funny pi shirt, Irrational number, march, march holidays, Math, math holidays, Mathematics, national pi day, pi, pi day, pi shirt, pi t-shirt, pi tees, science holidays