  The Topic: Pi Easier - Pi sounds like pie and is equal to about 3.1416. In math, this is the ratio of the circumference of a circle to its diameter. In other words, pi is a number that equals the quotient of the circumference of a circle divided by its diameter. Many people celebrate pi by holding a Pi Day on March 14th or 3/14.

Harder - The Greek letter pi represents the number by which the diameter of a circle must be multiplied to obtain the circumference. Pi is an irrational number. That is, it cannot be written as a simple fraction or as an exact decimal with a finite number of decimal places. However, you can increase the number of digits until you reach a number as near to pi as needed. Mathematicians with computers have calculated pi to millions of decimal places.

Pi is used in several mathematical calculations. The circumference of a circle can be found by multiplying the diameter by pi (c = pi X d). The area of a circle is yielded by multiplying pi by the radius squared (A = pi X r-squared). Pi is also used to calculate the area of a circle, and the volume of sphere or a cone. Math Library - Pi from The Math Forum, Drexel University
http://mathforum.org/library/topics/pi/
This huge site provides information and links to all kinds of information on the number pi.

Pi Mathematics
http://archive.ncsa.uiuc.edu/Edu/RSE/RSEorange/buttons.html
Find out the history of this odd number and discover some fun projects and activities you can do with pi.
Related Websites:
2) Finding the Value of Pi http://mathforum.org/isaac/problems/pi1.html
3) History of Pi
http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/Pi_through_the_ages.html
4) Joy of Pi by D. Blatner http://www.joyofpi.com/
5) Pi Pages http://www.cecm.sfu.ca/pi/

Ridiculously Enhanced Pi Page from Exploratorium
http://www.exploratorium.edu/learning_studio/pi/

Web Page Dedicated to Pi
http://www.wpdpi.com/index.shtml
This site has lots of great information on pi and was once featured in an article in the San Francisco Examiner, Partying for Pi by G. Smith.  Websites By Kids For Kids
Dale's Pi Page by D. Winham
http://www.geocities.com/SiliconValley/Pines/5945/
Here you find facts, news, history, notes, digits, songs, jokes, charts, poems, links and a program for pi.

More Pi Pages
Archimedes and the Computation of Pi from University of Utah
http://www.math.utah.edu/~alfeld/Archimedes/Archimedes.html
Related Websites:
2) Archimedes' Approximation of Pi
http://itech.fgcu.edu/faculty/clindsey/mhf4404/archimedes/archimedes.html

Digits of Pi
http://www.cecm.sfu.ca/projects/ISC/data/pi.html
This site provides pi to 10,000 digits and 50,000,000 digits.

Frequently Asked Questions About Pi from Dr. Math at the Math Forum
http://mathforum.org/dr.math/faq/faq.pi.html
What is pi? Who first used pi? How do you find it? How many digits is it?

Incredible Pi Code from I. Perterson's MathTreck, Mathematical Association of America
http://www.maa.org/mathland/mathtrek_4_1_00.html
This article focuses on codes derived by the substitution of letters of the alphabet for the digits.
Other Related Articles:
2) Eskimo Pi by K. Devlin from the Mathematical Association of America
http://www.maa.org/devlin/devlin_2_97.html
3) Passion for Pi by I. Peterson from the Mathematical Association of America
http://www.maa.org/mathland/mathland_3_11.html
4) Story of Pi by L. Mudehwe http://www.geocities.com/CapeCanaveral/Lab/3550/pi.htm
5) Slice of Pi, Anyone? by J. Shepler http://www.execpc.com/~shepler/piday.html

Paul's Page of Pi
http://www.escape.com/~paulg53/math/pi/
Most of the content of the site is focused on methods of calculating pi.
Related Websites:
2) Pi Pages http://www.cecm.sfu.ca/pi/pi.html
3) Slice of Pi by M.D. Huberty, K. Hayashi, & C. Vang
http://www.geom.umn.edu/~huberty/math5337/groupe/

Pi Irrationality Proof from Robert's Neat Math Pages
http://www.math.clemson.edu/~rsimms/neat/math/piproof.html
This site has a proof of how pi can be defined as an irrational number.

Pi Page by R.W. Clickery
http://www.ccsf.caltech.edu/~roy/upi/pi.html
Here you have a 'mere' 50,000 digits of pi, a few software programs for computing, and some quaint facts about pi.

St. Louis Pi Day by T. Chun, C. Daniel, and J.P. Kanoa
http://planetpi.8m.com/
Learn how this school celebrates the great number of pi.
Similar Website:

Partying for Pi by G. Smith from the San Francisco Examiner
http://www.sfgate.com/cgi-
Here is an online newspaper article about pi and pi day celebration.

Websites For Teachers
http://www.teachnet.com/lesson/math/geometry/circlesingeo.html
Grade school geometry doesn't have to get into a detailed lesson on pi to communicate the basics of this constant.

Chronological History of Pi with Developmental Activities in Problem Solving (Grades 7-10) by A.P. Solli from Yale-New Haven Teachers Institute
http://www.cis.yale.edu/ynhti/curriculum/guides/1980/7/80.07.11.x.html
The unit begins with a historical development of pi and proceeds with examples of activities to help students develop a deeper appreciation of the mathematical value of pi.

http://ericir.syr.edu/Virtual/Lessons/Mathematics/Geometry/GEO0001.html
This activity allows students to discover why pi works in solving problems dealing with finding circumference.
Related Lesson:
2) Introduction to Pi and the Area of a Circle (Grades 5-7) by E.R. Justice
http://www.iit.edu/~smile/ma96m4.html

Pi Day Celebration from The Math Forum, Drexel University
http://mam2000.mathforum.org/t2t/faq/faq.pi.html
Here are some activities you can use for a 'Pi Day' celebration on March 14 (3.14)?

Proving Pi (Grades 8-10) by G.D Williams
http://www.iit.edu/~smile/ma8719.html
This activity has students discovering the pi ratio by completing a circles activity.

What is Pi? by M. Kelley
http://www.middleweb.com/INCASEpi.html
Here you find activities to explore the meaning of pi. Pythagorus number American Pie diameter geometric shapes mathematics Babylon Archimedes Constant irrational number constant ratio digits ancient Egypt fraction infinite number transcendental number Eratosthenes decimal pie chart double helix pi cartoon fractal circle pi video circumference pie geometry tessellation 'Pi Day' 1:59 p.m. March 14 pi Created by Annette Lamb and Larry Johnson, 2/02.