pi
Get your pie on. Celebrate Pi Day on March 14. Pictured: World Pie Championship judge John Young at the 2007 pie competition in Dunfermline, Scotland. Reuters

Happy Pi Day! The mathematic symbol is celebrated every year on March 14. Why, you may ask? Because Pi represents the ratio of the circumference of a circle to its diameter … 3.14159, rounded off to 3.14.

Pi Day was started in 1988 by physicist Larry Shaw. Shaw worked at the San Francisco Exploratorium at the time, and the staff celebrated the symbol by reportedly “marching around one of its circular spaces, then consuming fruit pies.” In 2009 the U.S. House of Representatives recognized March 14 at National Pi Day.

Even if math isn't your best subject, there are other reasons to celebrate Pi Day -- like great deals and discounts! Some businesses offer free pie or discounts on 3/14. Check out some of the offers and promo codes available this weekend:

Pies

  • Buttermilk Sky Pie Shop in Tennessee (shipping available) is offering a $3.14 discount.
  • Pie Squared in Toronto, Ontario, will be offering free pies for an hour starting at 3:14 p.m.
  • The Flying Biscuit Café in Charlotte, North Carolina, is offering a free slice of key lime pie with the purchase of two entrees on Saturday, March 14.

Pizza

  • Papa John’s has 25% off some regular-menu items when you use the code “25OFF.”
  • Buy any pie for just $3.14 (limit one per person) at any Blaze Pizza.
  • Your Pie pizza chain customers can get a $3.14 discount on pizza orders.
  • Portland Pie Company has discounts and specials on Saturday, March 14, to celebrate Pi Day.

Random

  • Save $3.14 on any purchase from Amazon Local through Sunday, March 15.
  • Kaplan Test Prep is offering $200 off LSAT instruction courses in honor of Pi Day. Sale ends Monday, March 16. Use promo code PIDAY200.
  • The American Mathematical Society will be offering a discount on its publication. Use code MT159 for 25% off for nonmembers and 40% off for members.
  • Museum of Mathematics in New York City will have free activities, pie and hot chocolate on Saturday, March 14. Click HERE for more information.