Call me a nerd if you’d like, but I’ll unabashedly claim Pi Day as my absolute favorite holiday as a teacher! Obviously, I love the yearly excuse to eat a few bites of every kind of pie imaginable (so much so, in fact, that I’ve started hosting a yearly Pi Day party at my house since I’m not currently in the classroom!), but I’ve also really enjoyed creating an atmosphere of celebration and inquiry around a math topic that is best understood through hands-on work during a “holiday” that isn’t overly (or at all) commercialized.

Each year, I vary the activities I do with my students on Pi Day, but our celebration always includes a pie tasting – I send home a note earlier in the month asking families to consider sending in a pie – and a hands on investigation into the mathematical concept of pi. I’ve written two complete inquiry based resources for Pi Day, or any day that you’re learning about the formulas for calculating a circle’s circumference or area.

In fifth grade, I set out as many circular objects as I can find. I raid my kitchen, my classroom, and even the school gym and music room to collect circles of all sizes. Using a string and meter stick, students measure the length of each circle’s circumference and its diameter and record their work on a chart. The final column of the chart prompts students to use a calculator to divide each circumference measurement by the diameter length. After students measure lots and lots of circles, we discuss the ratio of diameter to length… essentially, we discover pi! You can easily replicate this lesson in your own classroom. If you’d like to use the materials I created, along with a teacher script for leading the discussion, click here to find them in my TpT store.

I definitely believe that Pi Day celebrations at school should include a focus on the mathematical concept of pi, but there are also so many ways to just experience the fun of this nerdy holiday. **Here are ten free and super easy ideas for celebrating Pi Day in your classroom:**

- Count down to
**Pi Minute**(New Year’s style, of course!) on 3-14 at 1:59 (because 3.14159**…**). Celebrate with a song**…** - Sing
**“Happy Pi Day to You”**to the tune of Happy Birthday. Then sing Happy Birthday to Albert Einstein, who was born on March 14, 1879. (You can search for Pi Day Songs on youtube.com for lots more ideas!) - Download this freebie and make copies of the included
**Pi or Pie? word search puzzle**and see who can find the most words. - Display 1000 Digits of Pi (a poster is included in the same freebie) and play
**Pi Digits Scavenger Hunt**. What strings of digits can you find in pi? Can you find your birthday (MMDDYY)? Your house number? Your zip code? If you can’t find it in the first 1000 digits, you can check http://www.mypiday.com or http://www.angio.net/pi/ to see where any string of digits first occurs in pi. - Have a
**pi digits memorization contest**. Make teams of 3-5 students. Display a copy of 1000 Digits of Pi or give each group a copy. Set a timer for 5-10 minutes, then see which team can recite the most digits correctly in order. - Tell some
**pi jokes**. What’s the official fruit of Pi Day?*A pi-napple!*What’s the official mascot of Pi Day?*A pi-rate!*What do you call a snake that is 3.14 feet long? A*pi-thon!*Your students can probably think of many more! **Discover Pi!**Measure the circumference and the diameter of several circular objects, like cups, frisbees, and coins. Then use a calculator to discover pi by dividing circumference by diameter. (For a full, standards-aligned inquiry lesson, see my Measuring Circles resource. You can also use cereal O’s to discover pi with my Investigating Circle Area resource.)- Go on a
**circle hunt**around the school. Look for big circles, small circles, concentric circles, and colorful circles. Try to find circles that have marks or objects that represent the center, diameter, radius, chords, arcs, or circumference. Or, see who can find the most circles in a set amount of time. - Convert as many numbers as you can into
**“units” of pi**. You’re 12 years old? That’s 3.82**π**years! (12÷3.14=3.82) How many**π**centimeters tall are you? **Make circle art.**Use colored markers to trace lots of different sized circles on white paper. Color some of the circles, or leave them all empty.

*You can download a free copy of this list along with a word search and pi digits poster in my TpT store!*

**Bonus Idea:** See if your school library has a copy of *Sir Cumference and the First Round Table* or *Sir Cumference and the Dragon of Pi*, math adventure books by Cindy Neuschwander. These are fun read alouds that introduce mathematical concepts relating to circles!

I hope you have a fantastic Pi Day this year, and I hope you’re able to find big or small ways to incorporate mathematical inquiry into your classroom celebration. Also, I hope you get to eat some really delicious pie!

**Have you tried any of these ideas? Or, do you have other Pi Day classroom activities that you love to do? Please let me know by leaving a comment below!**