Do you remember high school geometry? If so, you may recall that the circumference of a circle divided by its diameter is always the same number: Pi, aka 3.14159265... You can celebrate that infinite number on March 14, better known as Pi Day. That's the day math enthusiasts, students still learning math, and everyone in between celebrates the number Pi (and anything within a small radius of it).
On Pi Day, many restaurants across the US offer deals on all kinds of pie—pizza pie, cherry pie, pot pie, you name it. There are even events that celebrate Pi, pie, or other punnily Pi-related things. We've gathered up some fun deals and activities to help you and your kids celebrate this unique math-centered holiday. And if your child happens to be celebrating a birthday on or near Pi Day, check out these 60 birthday freebies for kids, including a free slice of pizza pie from Sbarro's!