Measure Round Objects Pi Challenge

Run it with one student or a small group, using string that does not stretch, a ruler, a calculator and 5 or more round objects. Students measure, divide, round to 2 decimal places and compare their results. The guide notes that results from 3.0 to 3.3 are close.

Two pages. Page 1 is an adult guide with the big idea, a materials list, a list of good round objects, 5 steps and a worked example in which a can 25.1 cm around and 8 cm across gives 3.1375, which rounds to 3.14. Page 2 is a recording table with columns for the object, distance around, distance across and around divided by across, plus a line for what students noticed.

Yes. We made it for 5th Grade holiday activities, and it works the same at home or at school. Families print it for one child and keep it where they will use it every day. Teachers print a copy per student or one for the whole room, whichever the day needs.

2 printable resources, all free to preview. There are 25 Pi Day resources in all, from Kindergarten to 5th Grade, gathered on our Pi Day activities page. Downloads are included with a ClassWeekly free trial, and every page prints on standard 8.5 x 11 paper.

These are written for 5th Grade students, roughly ages 10-11. Many teachers also use them a grade up for review or a grade down as an extension, so use the preview to judge the fit for a particular child.

Yes. Nothing here assumes a classroom of 25, so they work the same one-to-one at the kitchen table as they do in a 5th Grade classroom, a learning center, or a tutoring session.