Pi Day, celebrated every March 14th (3/14), honors the value Pi, otherwise known as 3.14….

Students are often familiar with the value of Pi, but they may not understand its meaning or where the value comes from. Pi is actually the ratio of the circumference of a circle to its diameter. In other words, if you measure the circumference of any circle, and divide it by its diameter, assuming accurate measurements, the resulting number will be close to Pi, or 3.14159….

For this InspireData activity, students will work in pairs or small groups to measure the circumference and diameter of circular objects in the classroom. They will enter their data into the InspireData table, either directly or via the e-Survey. A field is already set up in the table to find the quotient of these two measurements for each object. In Plot View, students can analyze the relationship between circumference and diameter, discovering that the ratio is always close to 3.14. Discuss sources of measurement error that might lead to values larger or smaller than pi.

A video demonstrating how to use this database in the classroom can be found on Teacher Tube.

The database template, Pi Day.idf, can be found by clicking on the yellow Download File button. To see a completed example with sample graphs, open Pi Day Exemplar.idf (listed below as an attachment).

Materials:
-String
-Measuring devices (tape measure, ruler, yard and/or meter stick)
-Objects of different sizes with circular edges (plates, cans, CDs, lids, bowls, bicycle wheels, cups, clocks).

Adaptations:
-The instructions within the database template specify measuring in centimeters, rounded to the nearest millimeter. Depending the age and measuring abilities of your students, you can change the unit of measurement and the level of accuracy required.
-Assign the measurement of circular objects as homework. Students can measure objects at home and enter their data via an e-Survey that is posted to the web.

This activity was created using InspireData 1.5, which must be installed to open the files. Download a 30-day free trial at www.inspiration.com/freetrial or if you have InspireData 1.0, download a complementary upgrade.