...no, not the round apple kind but the math constant 3.141 kind.
The number π is a mathematical constant, the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. Wikipedia
As math is celebrated around the world, PBS LearningMedia is launching a collection of fun, free math resources for educators in a “Math Is Awe-sum!” collection. The new collection is available online at www.pbslearningmedia.org/