Without the Exploratorium, we might never have had an official Pi Day celebration. In 1988 Exploratorium physicist Larry Shaw started the tradition, and it was finally recognized by Congress in 2009. The Exploratorium highlights some great hands-on activities, and there is also a great list of Pi-related links.
Multiplication Rock! Songs from Schoolhouse Rock - the song AND the lyrics! Play the song and print out the lyrics for FREE! at this site! http://faculty.kutztown.edu/schaeffe/Mnemonics/MultRock/multrock.html
A game for 2 or 3 players. Each player chooses a color pencil they will use in the game. Players take turns rolling the dice, using the numbers that they rolled to draw the perimeter of a rectangle or square writing the area in the middle of the shape. Game ends when players run out of room to draw. Winner is the player who has used the largest area/most squares.