Can't Keep Calm Because I'm Irrational Shirt. Math T-ShirtsMachine wash cold with like colors, dry low heat On Pi Day wear this funny math joke tshirt This tee is a great gift for your teacher, parents, friends or children. Wear these shirts to a school math event, work or around the house! Go Pie! Sizes and Colors for all! Men, Women, Boys, Girls and kids sized tshirt as well. Lightweight, Classic fit, Double needle sleeve and bottom hem We use high quality and Eco friendly material and Inks! We promise that