In past years, math teacher Kevin O’Gorman has celebrated Pi Day with his classes. It’s a day that celebrates the symbol pi (π), which represents the ratio between circumference and diameter. Pi is an irrational number that has no end and no repeating patterns. It’s used in formulas for circles, cylinders, spheres and cones.

Resources like piday.org offer ways to learn about pi by seeing one million digits of it, testing how many digits you know and offering a section of their website called Celebrate Pi with merch and activities for Pi Day.

“As far as what we do curriculum wise, I’ll show a video to them about where pi comes from,” O’Gorman said. “The video talks about when it was first discovered back in the ancient times when people had to discover that number of infinite digits by hand.”

From the video, O’Gorman has always wanted his students to take away the uses of pi. To help encourage that, he would get treats for his classes.

“I would buy these little mini pies for the class with some whipped cream,” O’Gorman said.

Although he can’t always celebrate with his classes due to the timing of Spring Break or the testing schedule, O’Gorman finds it important to show the background of math symbols anytime he can.

“Anytime we can try to show where a symbol is coming from, [why] we use math or anytime you can bring some fun into math, you should,” O’Gorman said.

Once he started learning more about pi, O’Gorman started enjoying Pi Day more. Based on his history of celebration, O’Gorman has advice for people interested in celebrating.

“Celebrate it fully. Have a slice of pie, do a little research about where pi comes from, get a little bit of knowledge behind it,” O’Gorman said.

In St. Louis, Pi Day is celebrated with local restaurants offering discounts on pizza and specialty pies for the spring season.