March 14th is the birthdate of Albert Einstein. It is also the same date that people around the world celebrate the mathematical constant pi with Pi Day. Pi Day was founded in 1988 by Larry Shaw, a physicist from Exploratorium, a San Francisco interactive science museum and became an official national holiday in 2009. Pi is the ratio of a circle's circumference to its diameter and is represented by the Greek letter π from the first letter of the Greek word perimetros (circumference). It is an irrational, transcendental number that cannot be decisively defined as a common fraction and its decimal form goes on forever with no obvious repeating pattern. Typically, when used in math problems, it is represented numerically either with the fractional form of 22/7 or the decimal form of 3.14. Because of its uniqueness, mathematicians, scientists and others have been fascinated with pi and use March 14 to celebrate and educate others about pi. Here are some great places to share pi with you kids and have your own celebration of Pi Day.
Exploratorium – Pi (π) Day Activities – At this page you will find four activities including "Cutting π," "Discovering π," "Tossing π," and "Searching π." Look to the left side menu to find more information about Pi (π) Day, the history of pi and more.
Teachπ.org – This website provides an abundance of ideas and information all about pi. Use the upper menu to find craft ideas, lessons, music and art, stories, additional links and much more. There is even a list of students who have memorized pi a certain number of digits (one 11th grader recited out to 10,980 digits after the decimal point. WOW!)
NCTM.org - Celebrate Pi Day with NCTM – Here you will find lesson plans, ideas, and printables to help you explore pi with your student arrange by elementary, middle and high school learning levels.
The Joy of π – A companion website to the book of the same name, there are links to other sources for related information, lesson plans, history, activities and more.
Pi Day Activities PDF from the School District of Philadelphia – This 12-page downloadable PDF on the Internet Archive Way Back Machine, provides ideas and printables for activities, books to read and more for kids in kindergarten through high school. (To save to your computer, right click on the PDF and "Save As" to your file.)
MathWorld – Pi – Explore the number theory of pi with the information provided for a variety of algorithms, formulas, and more. If your child is thinking about memorizing pi, check out the "Pi Wordplay" link for some mnemonic devices that might be helpful. Please note that this website is probably best suited to the older student whole enjoys higher level mathematics.
PBS Teachers' Lounge – 21 Pi Day Resources for your Classroom – This is a great list of lessons, videos, activities and links for your pi studies.
Edutopia – 7 Classroom Resources for Pi Day – Matt Davis from the George Lucas Foundation has put together this list of websites for pi resources.
We Are Teachers - 31.4 Mathtastic Pi Day Activities for the Classroom – You will find games, activities, projects and more among this list of ideas for making Pi Day fun.
Math Geek Mama - Pi Day: Huge List of Pi Day Activities for All Ages – Still looking for just the right resources for Pi Day? Then check out this wonderful list of art projects, games, worksheets and more.
NASA Jet Propulsion Laboratory – California Institute of Technology – This is a filtered list of over 45 pi related lessons and/or activities, most of which provide visual aids, downloadable worksheets and answer keys and suggestions for other related learning extensions.
Please note that some of the resources at the various sharing websites do overlap, but they all have some unique ones not mentioned separately in our list.