Tomorrow is March 14, better known to math teachers as Pi Day. (It’s 3/14 — get it?) The last year I taught in Tulsa, Pi Day coincided with an accreditation audit, so I put together a whizbang lesson plan to entertain the kids and impress the accreditation auditors at the same time. If you teach math, and you’re looking for something pi-themed to do with the kids tomorrow, this lesson comes together easily and appeals to multiple learning styles.
Activity 1: Grab an assortment of cylindrical objects (Coke can, roll of tape, glue stick, toilet-paper roll, aerosol can, whatever), a piece of string, and a ruler with English and metric measurements.
Give the kids the definition of pi (the ratio of the circumference to the diameter of a circle).
Ask the kids to use the string and ruler to measure the circumference and diameter of each object in inches, centimeters, and millimeters. Then ask them to use this data to find the ratio of the circumference to the diameter of each item in inches, centimeters, and millimeters.
Have them share their findings, then ask them what they notice (e.g., the smaller the unit of measure, the closer they get to 3.14). Ask them to write a paragraph explaining their findings and any theories they have about them.
Activity 2: Using a long piece of string, a piece of chalk, and some kind of anchor (I used a carriage bolt inserted into a CD spindle weighted down with marbles), create a makeshift compass. Have the kids use the compass to draw the largest circle they can make on a concrete surface. (If the weather is dodgy, you can roll out butcher paper in a lobby or gym and use a marker to draw the circle instead.)
Ask the kids to use available tools (rulers, yardsticks, calculators, string, tape measures, etc.) and their knowledge of pi to find the diameter and circumference of the circle.
Because I like to spoil my kids, I ended our Pi Day lesson by handing out homemade whoopie pies, but this is obviously completely optional.