Pi,
Greek letter (
),
is the symbol for the ratio of the circumference of a circle to its diameter.
Pi = 3.1415926535...
Pi Day is celebrated by math enthusiasts around the world on March 14th.
The Exploratorium's 2009 21st Annual Pi Day Celebration page
Pi Song
(sung to the tune of American Pie)
http://www.piday.
Here's more Pi songs:
http://mathforum.
Pi Day Resources
http://www.mobot.
Pi Day Ideas
http://www.quia.
Plan a Pi Day Party
http://www.educatio