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As you likely know, March 14th is dedicated to the number Pi (π), due to its international date format: 3/14. Furthermore, UNESCO declared it the International Day of Mathematics. Pi Day is a great opportunity to promote connections between math and all kinds of fields, concepts, and, ultimately, the world around us.
That’s why we’re bringing you ideas and activities from our curriculum for all grade levels, so you can celebrate it in the classroom with your students. Let’s get started!
Contents
Pi Breakfast and Snacks
Here’s a suggestion for the whole school—and a great way to get families involved: encourage students to bring in math-themed snacks. This is a wonderful way to boost creativity by inviting students to give their snacks an original title. At Innovamat, we celebrate this every year. In case you’d like to do the same, here’s a template you can adapt.
Pi Bracelets
You can also get excited about working on counting with… Pi bracelets. The activity consists of making bracelets using as many pieces of the same color as the corresponding digit of the number Pi (π).
Pi-ems and Pi-poetry
If you want to foster your students’ literary creativity, you can organize a Pi-ems (or Pi-stories) contest—flash fiction where the number π is hidden. In these stories, each word in sequence must have the number of letters corresponding to the digits of π.
If you prefer to play with rhythm and meter, try Pi-poetry, where the number of syllables per line follows the same mathematical sequence. Whether they write a short triplet (3, 1, 4) or a complex stanza, students will have to count, clap, and carefully choose their words to match the irrational rhythm of the day. It’s a perfect way to integrate Math and English Language Arts (ELA), showing that even the most famous constant in geometry can inspire a masterpiece!
Several Circles
Explore the infinite beauty of circles with Wassily Kandinsky’s Several Circles, a masterpiece from the Guggenheim Museum in New York.
This iconic artwork is the perfect visual prompt for students of all ages to observe, measure, and discuss the geometry that surrounds us. From the smallest point to the largest sphere, it’s a stunning reminder that mathematics is the secret language of art.
Continuing with art connections, you can decorate the school with decimals and play with them: you can assign a color code to each number and create a visual representation of Pi.
Here is an example:
The MoMath Pi Day Puzzle
Can we measure the “unmeasurable”? This activity, inspired by the National Museum of Mathematics (MoMath) in New York City, brings a classic logic puzzle into the world of irrational numbers.
Exploratorium: The Birthplace of Pi Day
Did you know Pi Day started at the Exploratorium in San Francisco? Their portal offers a unique blend of science and art, from calculating π by tossing toothpicks to exploring the history behind the number.
It’s the perfect place to find multisensory activities that prove math is a living part of our culture.
NCTM: Expert Classroom Resources
The National Council of Teachers of Mathematics (NCTM) provides a curated collection of high-quality lessons and interactives. These resources are designed to help students move beyond the formula and explore the true ratio of a circle.
Whether you need digital tools or inquiry-based challenges, the NCTM offers pedagogical support for every grade level.
Innovamat Sessions
You can find various sessions in the Classroom Manager where students will discover π through a range of activities.
The Circumference
For 5th grade, students can use everyday objects to discover that the ratio between the circumference and the diameter of a circle is π.
5th Grade Session
Find cylindrical objects of various sizes and divide their circumference by their diameter.
And we’re moving forward with another activity for upper elementary! Students can discover the area of a circle by breaking it down into different sectors!
Pi Day Session
For middle school level, we’ve put together one activity for each grade.
We’ll begin with a 7th-grade activity. If you love bringing puzzles into the classroom, this activity is perfect for you. In this session, students work with the decimal expansion of π within the context of a celebration.
The specific goals for this session are:
- To review the relationship between π and the circumference and area of a circle.
- To reflect on the infinite nature of the decimal expansion of π.
- To discover various fun facts about the number π.
7th Grade Session
Using pentominoes, students complete a Pi-shaped puzzle. They’ll soon see that all the numbers on the pieces are closely related to Pi…
8th Grade
We continue with 8th grade, featuring an activity where we calculate the area of a circle through probability and hands-on experimentation.
The specific goals for this session are:
- To discover the number Pi through a probabilistic experiment.
- To make estimates for a probability problem and refine them based on experimental results.
To relate probability to the measurement of the area of plane figures.
8th Grade Session
If we randomly drop 100 grains of rice onto this box, how many do you think will land inside the circle?
9th Grade
For 9th grade, we’re diving into the exciting world of approximating the famous irrational constant! In 2022, Emma Haruka calculated the value of π with the most precise approximation to date: 100 trillion digits!
If we wanted to write them all down on paper, how many sheets or books do you think they would fill? 🤔
Specific goals for this session:
- To revisit the relationship between Pi and the calculation of a circle’s area.
- To practice strategies for calculating the area of circular figures and applying the Pythagorean theorem.
- To introduce the concepts of absolute error and relative error.
- To reflect on the irrational nature of Pi and the infinitude of its decimal expansion.
9th Grade Session
We’re working with the number Pi in a celebratory context, from both a numerical and a geometrical perspective! We’ll revisit Pythagoras and area calculations, while introducing the concepts of absolute and relative error.
10th Grade
Finally, in 10th grade, we’ll draw on all the knowledge we’ve built about the number π and discover even more fun facts!
Specific goals for this session:
- To review and consolidate the knowledge of π developed throughout elementary and middle school.
- To engage in productive practice of multi-step operations involving the number π
10th Grade Session
How many digits of π do you think NASA uses for its calculations?
As you can see, there are plenty of fun and clever ways to bring Pi into the classroom and connect it to many different fields and disciplines, all while encouraging participation and creativity. Do you have more ideas or activities you’d like to share with us? Share your results with us on social media, and have a fantastic Pi Day!
And if you are as fascinated by the world of Pi as we are, be sure to read The Discovery of Pi: From Ancient Civilizations to the Classroom.
Pi Day Frequently Asked Questions (FAQs)
Pi (π) is the number that connects all the circles in the universe: it expresses the ratio of a circle’s circumference to its diameter. Its approximate value is 3.14, but it has infinite decimal places. Without Pi, we wouldn’t be able to calculate areas, design wheels, or understand many physical phenomena.
The idea originated in 1988 with physicist Larry Shaw at the San Francisco Exploratorium. Shaw wanted to make math more accessible and fun for the general public, organizing a celebration that included eating pies and parading around a circular space.
It is celebrated on March 14th due to a clever visual play on the calendar: in the US date format, March 14th is written as 3/14, which matches the first digits of Pi: 3.14. This coincidence turned an ordinary day into an international math holiday.
Coincidentally, March 14th is the anniversary of Albert Einstein’s birth (1879). This fun fact adds special value to the date, uniting geometry’s most famous constant with the legacy of modern history’s most influential physicist.
The approximate value of Pi is 3.14159… Pi is an irrational number. Its decimals are not only infinite, but they also never repeat in a pattern. This characteristic makes it an ideal concept for explaining the difference between the exact and the infinite to students in the classroom.
It is the perfect opportunity to learn math through hands-on classroom activities, challenges, and experiments with circles. Through creative projects adapted to each educational stage, student participation and the discovery of the number Pi are encouraged in a fun way.
