On March 14, math classes across the country will celebrate Pi Day—a national holiday in honor of the mathematical constant pi, which represents the ratio of a circle’s circumference to its diameter and starts with the digits 3.14.
It’s a time when students can take a break from a traditional way of learning about math and get more creative using pizza, pies, and more.
“[Pi Day is] to remind kids that there are fun aspects about math,” said Joseph Bolz, a math teacher at George Washington High School in Denver.
Education Week spoke with three educators about how they’re celebrating Pi Day in 2025.
In Colorado, a Pi Day celebration is growing this year
This year, Bolz is excited about the expansion of Pi Day in his high school.
In previous years, he would spend half of the math period creatively teaching about pi—for example, using hands-on tools to measure the angles and radius of a cookie—to make it easier for kids to understand, Bolz said.
In the other half of the period, Bolz’s students would go to the library, where they’d meet other math teachers, students, and parents, and engage in Pi Day festivities.
Students would grab pie and create a pi chain, write jokes about pi and math, or decorate a pi skyline, with numbered buildings in the order of pi.
“It’s always amazing when I can see the kids’ faces when they’re coming into the library [in reaction to] all the different stuff that we have,” Bolz said.
Parents and local businesses donate and volunteer to create a memorable Pi Day celebration, Bolz said. But this school year will look a little different as the high school has a sponsor: T-Mobile.
“[T-Mobile is] going to bring a truck that has a bunch of science and engineering gear so I’m trying to get my science classes involved in Pi Day that way,” he said. This will create a cross-departmental celebration of Pi Day, with both science and math, he added.
In Illinois, students compete in Pi Day activities
In the Chicagoland area, Catalina Perricone, a high school math teacher currently on maternity leave, has celebrated Pi Day for more than 12 years throughout various schools in the region.
“It’s important for students to know the historical importance [of pi] and how closely it’s tied into such big concepts like circumference and radius and area, and that’s it’s been known for generations and evolved for so long,” Perricone said.
Perricone has celebrated Pi Day through hands-on activities like having students collect, measure, and calculate circular household items like a Pringles can or roll of paper towels.
But one celebration that sticks out is competition-based activities, like Jeopardy games and trivia or department-wide contests. Another one of Perricone’s favorite pi-related activities is having students draw a circle using their arm as the radius and voting on who drew the most perfect circle.
“Students really get into it,” she said. “They get very competitive, which I love.”
She is excited to get back into the classroom and celebrate another Pi Day.
“Math isn’t always the [most fun] for students, so if you are going to make it fun for them, make it tangible for them,” she said. “Then they’re going to be excited as well.”
In New Jersey, Einstein’s birthday is a key part of the day
In Princeton, N.J., the community gets together to celebrate PI Day along with Albert Einstein’s birthday, who lived in the town.
For the last 15 years, community partners and local organizations have put together a series of events throughout the day and around town related to both pi and Einstein.
Many Pi Day events are held at the Princeton Library, which is at the center of the town, bringing together teachers, parents, and kids. (When Pi Day falls on a weekday, like this year, the celebrations are held on the weekend.) The library curates educational materials and hosts events like Einstein Story Time, and pi-iku, in which students make haikus about science or math.
“We try to mix it up every year and think of different ways we can highlight both the number pi as well science and math in general,” said Janie Hermann, the adult programming manager at Princeton Public Library.
The library also displays relevant books and sends a list of ones about pi or Einstein to teachers in the community.
“There are some people who are just interested in the math aspect and that’s great, but by broadening it and trying to tie it into books and making it a broader scope, you’re going to attract more people to the topic and maybe then they can discover something about math and science,” Hermann said. “Maybe they can discover something about pi and its importance and what it is.”