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Pi Day

Pi Day

Whether you’re an engineer, button maker or woodshop hobbyist, you need pi!

Why so much hoopla around an irrational, never-ending number? Pi (3.14159…) has been around for at least 4,000 years, even used by Babylonian and Egyptian architects. In 1988, Exploratorium staff physicist Larry Shaw declared March 14 (3.14) Pi Day—and its grown to an international event. We’re here to help you celebrate.

Start a pi-filled day with the Pi Shower Curtain, and chill your juice with ice from the Pi Ice Tray. Bake a pi-shaped (π) cake with the Pi Baking Mold. Wrap your favorite math geek’s present in the Matrix-themed Pi Gift Wrap. Learn great math facts for your pi party by reading David Blatner’s Joy of Pi and John D. Barrow’s book Pi in the Sky. Tackle the challenging two-sided, circular Pi/Pie Jigsaw Puzzle, and make Archimedes envious by cutting precise slices using the Pizza Pi Cutter