03/14/2023 by Carney Sandoe Staff |

Celebrating Pi Day

Pi Day is the quintessential math holiday.

March 14 written numerically is 3/14, as in 3.14, the first three digits of pi’s endless sequence of numbers. On Pi Day we celebrate the constant that tells us the ratio of a circle’s circumference to its diameter. The first people to refer to the ratio between the diameter and circumference of a circle were the ancient Egyptians. It took 1,000 years to prove pi irrational, and today pi has been calculated to over one trillion digits past its decimal point!

This ‘holiday' (which also happens to be Albert Einstein's birthday) has been celebrated since roughly 1988, and on March 12, 2009 the U.S. House of Representatives passed a resolution declaring every March 14 “National Pi Day.”

We work with math teachers across the country to find them their next (or first!) math teaching jobs, and have the pleasure of hearing about some amazing math activities they plan for their students. In honor of this fun (and delicious) holiday, we've compiled some of our favorite pi-related classroom activities that make the most out of this best-known math holiday.

Check them out below and share what you're doing in your own classroom by tweeting to @carneysandoe so we can feature your classroom. (And remember, you can also enjoy these activities year round, not just on Pi Day.)

Mathematical Measurement

Since pi is so closely related to measuring circles, younger students can celebrate Pi Day by exploring measurement. Students can investigate how to measure big things and small things around school. If you use this activity to celebrate Pi Day, challenge older students to measure not only length and height but also to measure all the way around such objects as round tables, playground equipment, and other circular items found in real life.

Read from the “Sir Cumference” Book Series

Any teacher will love how insanely adorable and clever these books are. Join Sir Cumference, Lady Di Ameter, and their son Radius for wordplay, puns, and problem solving in this geometry-packed math adventure. Good for grades 1-7, even older students will have your full attention.

Discovery of Pi: How is it Derived?

Have students work with a partner to derive pi using round discs and yarn. Give each group some yarn, a disc of some sort, and a pair of scissors. Students should wrap the yarn around the circumference of the circle. Then, have them see how many diameters of their circle they can cut from their circumference. Students will find that they can only get three full diameters and will have a small piece of yarn leftover. This represents the 3.14159… Each group will get the same results regardless of how big or small their circle is, and will discover that the formula for pi is circumference divided by the diameter. You can use any circular object you can find in your room (Pringles lids, coffee lids, cup bottoms, cans, etc.) or have students bring in something round from home.

Turn Pi into Music

This experiment attempts to convert the first 10,000 digits of pi into a musical sequence. Great for partnering up with your school's music teacher, see how far your classroom can take this activity.

Investigate Pi 

Use this awesome Pi Day Investigation freebie on a bulletin or white board. Have students use tablets, computers, or their phones to find answers to the questions. For a group activity, have each group choose 3-5 questions to answer from the list and then write their answers on the sheet. Hung the sheet around your room or in the hallway so other students can read about Pi Day.

Pi Day Coordinate Graphing Picture

Here's another great activity where students graph points on a coordinate plane to create a picture of the pi symbol with “Happy Pi Day” at the bottom. The clever title of “Stop Being So Irrational!” gives students a clue to what the picture will be. The points include ordered pairs from all four quadrants and decimals. Download it here.

Pi Day Sudoku Challenge

Your students will have fun solving a Pi Day version of Sudoku. Download the PDF here.

Hold a Pi Day Fundraiser

Sell slices or pizza or pie to students, teachers, and parents for $3.14. Raise money for your school's favorite cause.

Rational vs. Irrational Numbers

This texting activity for rational and irrational numbers is designed to help students build a better schema about irrational numbers, including pi. It’s a fun and engaging activity where students create a texting conversation related to rational and irrational numbers. This gives creative students a chance to shine, and is great for middle school students.

Write a Pi-ku

Great for math and language arts teachers alike, writing a pi-themed haiku is a fun way to blend poetry and math themes.


If all these activities tired you out a bit, don't worry: you can rest up on World Sleep Day which is always around this time of year. Organized by the World Sleep Day Committee of World Sleep Society, World Sleep Day takes place the Friday before the Spring Vernal Equinox of each year.

Are you a math teacher looking for your next teaching opportunity? Contact us today to become a job-seeking candidate with CS&A. We help you find a job in a school community where you'll thrive and be able to share you love of math with students who are equally committed to learning. Learn more about our free teacher placement service!

Back to Blog

Leave a Comment


There are no comments on this blog entry.