Eratosthenes Finds the Circumference of the Earth

My students will be calculating the circumference of the Earth, ala Eratosthenes (who did his work over 2200 years ago).

Setup: put a few key facts on note cards and hand them out to a few students. Give everyone a copy of the task sheet.

Challenge the class to bring you the circumference of the Earth before class ends. I promise you the students will accuse you of giving them too little information. Don’t let ’em get away with it. Encourage them to dig deep — into knowledge they learned before this class (gasp!).

Calculating the Earth's circumference

Get the task sheet (pictured above right) on Scribd, “Task – Eratosthenes Measures…”

Note: This project was based on a Georgia Performance Standards task that I felt was too prescribed and (frankly) boring.