Pi Day is coming! Be ready on March 14 with our Pi Day T-shirt. Featuring the Pi symbol over the date inside a delicious pie crust. Pi Day was originally founded in 1988 and then officially adopted by the united states in 2009. The Pi Day T-shirt makes a great gift idea for any engineer, student, physician, math teacher, dad, mom, geek, nerd, husband, wife, teacher, student, friend, baker, or anyone who loves science and math or just loves to bake and eat pie! Let's be irrational!