Fun Fact: 3.14 is Pi and March 14th (also known as 3/14) is Pi Day.
Pi is a very special ratio, which calls for a very special holiday! Pi is the ratio of a circle’s circumference (distance around the circle) to its diameter (distance across the circle). While we usually shorten it to just 3.14, the ratio is actually never-ending! In 1988 American physicist, curator, and artist Larry Shaw and his friends held a party to honor pi for the very first time, and in 2009 the United States government officially recognized Pi Day as a special observance. Now people around the nation, and world, can join in on the fun.
Check out some thought-provoking videos, interactives, games and activities below to celebrate Pi Day with your family or classroom!
Learn All About Pi
Cat Likes Circles – Peg + Cat | PBS KIDS Lab
Grades PreK-K
This video from Peg + Cat will help children recognize and identify 2D shapes such as circles, triangles, and squares. Cat sings a jazzy tune about how much he likes circles.
Relationship between Diameter and Circumference
Grades 3-5
The CyberSquad is trapped in one of the Spheres of Fears, and they are trying to get through a gate to escape. The key to the gate is locked inside a can, and in order to access the key they must attach the correct label to the can. After guessing incorrectly on the first try, the CyberSquad decides to take some measurements to find the correct label. They realize there is a special relationship between the circumference of a circle and the length of its diameter.
Formulas for Circle Area and Circumference: Simple as Pie
Grades 6-7
In this video from Cyberchase, Bianca and her friend team up to sell pies. Bianca learns that pie-pan sizes are the measured diameter of the pan, but that there is a mathematical relationship between the diameter of the pan and the circumference of the pan. In the accompanying classroom activity, students calculate the circumference of a variety of wheels.
Calculating Pi with Darts | Physics Girl
Grades 6-12
Pi can be calculated using a random sample of darts thrown at a square and circle target. The problem with this method lies in attempting to throw “randomly.” Watch as Dianna Cowern, host of Physics Girl, explores different ways to overcome her errors.
Pi & The Fibonacci Sequence
Grades 6-12
Explore intriguing appearances of pi and the Fibonacci sequence outside of mathematics in this video from NOVA: The Great Math Mystery. Although well-known in mathematics, the numbers of the Fibonacci sequence are also frequently found in the natural world, such as in the number of petals on flowers and the number of spirals of a pinecone. Pi is commonly recognized as a number that relates a circle’s circumference to its diameter but it also appears in many other phenomena.
Activities, Crafts and More
Paint-a-long – Peg + Cat | PBS KIDS Lab
Grades PreK-K
Use this art activity from Peg + Cat to understand shape attributes, composition and decomposition of shapes. Children can combine shapes to draw Peg, Cat, and all their friends. Peg can help children every step of the way as they use their paintbrush and different colors to draw snazzy shapes or colorful characters—or, she can leave them to make their own beautiful painting.
Odd Squad Creature Duty Game
Grades 1-3
This game from Odd Squad will help children with identifying shapes, sorting and classifying, and using the partitioning of an object, like a sandwich, to represent portions of a whole.
Geometry of Bubbles | Lesson Plan
Grades 3-8
Help kids learn how to determine the diameter and circumference of a circle using these media resources and mathematic Bubble Art Activity.
Square-Wheeled Tricycle: Radius and Circumference
Grades 7-8
Uncover the secret behind how a square-wheeled tricycle can work at the National Museum of Mathematics. This interactive exercise focuses on working with the radius of various circles to find the circumference and area as well as challenging you to find the distance a square wheel travels around the track.
A Slice of Pizza Science! | It’s Okay to Be Smart
Grades 6-12
How does math keep a folded slice from drooping? And what does pizza have to do with the speed of light? In honor of Pi Day, order an extra large pizza – it’s scientifically proven to be the right decision! And if you want to make your own pizza pi, try this great recipe from PBS Food.