Pi Day is celebrated on March 14th each year. March 14th can also be written as 3/14.

There are three measures that can be taken to better under the nature of a circle. You can determine the linear distance that is covered by the circle itself that measure is called the circumference of the circle. If you were to draw a straight line through the center of the circle and touch each end of the circle this distance is called the diameter. The distance from anywhere on a circle to the middle is called the radius of the circle. A Pi symbol as a visual symbol that encompasses the ratio of the circumference of a circle to that of its diameter. The Pi symbol is also the sixteenth letter of the Greek alphabet. Since it is a ratio it does not matter how large of a circle you have, it is always set to the same ratio. Pi can be used to learn much more information about a circle, if you have only a few measures of the circle. The ratio converts to 3.14 (followed by a repeating decimal.)

On March fourteenth every year many math teachers tend to recognize this day as Pi Day (Math 14th = 3/14). See the irony in the date that Pi Day is celebrated on? The idea for the celebration was developed by a test preparation company. It gained steam in the math teacher community and is a staple at most high schools.

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Pi Day Worksheets

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Pi Day Word Problems

Mary makes two blueberry pies in two pie pans that are 6" in diameter. What is the total area of Mary's two pies?

Five Questions About It

The tire on Jason's bicycle has a radius of 12 inches. What is the circumference of the tire? How did you find the answer?

History of Pi Day

People have used ℼ to calculate the circumference of a circle for about four thousand years. Archimedes, the Greek mathematician, worked on making the number ℼ more accurate around 200 BC.

Fun with Pi

Some mathematicians have calculated pi out to 10,000 digits. That’s a lot of numbers! To get an idea of how big pi actually is, try the following class activity. Make a ℼ paper chain. Each link of the chain should have the next successive number of pi written on it. How many links are in your class' chain?

Cookie Day

Some people celebrate Pi Day by eating pie. Apart from the fun pun, it's because ℼ is the ratio of a circle’s circumference (C) to its diameter (D). If you know one of these quantities, because the ratio between them is known, it is always possible to find the other.

Pi Problems

Calculate the volume of a pie that has flat sides so that it is shaped like a cylinder. The pie has a radius of 3 inches and a height of 2 inches.

Find the Diameter, Radius, Circumference, and Area.

Measure the diameter of each pie. Find its radius, circumference, and area.

Pi Day Trivia

When did the U.S. make Pi Day a national holiday?

Circumference and Area

Henry has a hula hoop with a radius of 14 inches. What is the circumference of his hula hoop?

Volume Problems

Find the volume of each cylinder.

Cookie Problems

What is the circumference of a sugar chip cookie with a radius of 2 inches?

At the Bakery...

If you cut the pie into 6 pieces, what will be the surface area and volume of each piece?

Blueberry Pi Day

What is the volume of a blueberry pie with flat sides if the pie is 2 inches high and the diameter of the pie is 11 inches?

Pi Day Quiz

What information do you need to know about a cylinder in order to calculate its volume?

A Real Mix and Match

Find the height of a piece of pie with flat sides where the volume of the whole pie (later cut into 6 pieces) is 90.432 cubic inches and the diameter of the whole pie is 8 inches.