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Pi Day (March 14)
This guide has videos, online interactives and lesson ideas for Pi Day.
Why is there a special day for Pi, the ratio of a circle's circumference (distance around the circle) to its diameter (distance across the circle)? What makes Pi so special?
The objective of this website is to convince the world that mathematics is fun and bring attention to mathematiciansâ€™ favorite number, Pi. Learn about Pi, watch some videos and see some Pi in action.
Did you know that we've known the number of pi for over 4,000 years? Or that the number represented by pi has infinite numerals? This video explains how pi is connected to the study of music, financial models, and even the density of the universe.