How I taught Eratosthenes in a Face-to-Face Classroom

One of my favorite books to read to my middle schoolers was The Librarian who Measured the Earth by Kathryn Lasky.Eratosthenes - The Librarian Who Measured the Earth

And I read it to each of my classes before starting our study of the Layers of the Earth. There were a couple of reasons for that placement. First, it was the start of studying the content of Earth Science, and particularly the geosphere for the rest of the first semester, and I hoped to reference the ideas in the book over the course of the year. Second, I wanted to tie trade books in early and this is the one with the strongest content ties. In the interest of full disclosure, this was not the first thing I did with my students, but rather a launch into content. By the fourth-sixth week of school we had worked on the importance of lab procedures/safety, tools for measurement this year (plus a brief sanity survey of measurement), started vocabulary study, and finally taken a strong, baseline look at density.

*I’m sure I’ll insert pictures of my plan book here eventually* Reference my lesson plans HERE. The last year I taught this was: 2009.

And if my students can get past that stylish scientist, they can start to appreciate the thought which went into what Eratosthenes proved. Well, I think it is worth laying down the background knowledge for when those middle schoolers realize that later on maybe more accurate. This works well as an introduction to the rotation/revolution of the Earth, Moon; seasons, unequal heating of the Earth’s surface.

More advanced students might realize all the fore-thought of this little experiment carried out by Eratosthenes. In this teacher’s dreams, students might put together all the below elements and we cruise through March as a class. Yet sometimes I still humored my administrators by calling out these little tie-ins to Eratosthenes as we move through the science content instead of packing it straight in (haha).

How would I do Eratosthenes in a Blended Learning Classroom?

I would still use a hard cover book to introduce the idea of Eratosthenes. I used hard cover books for durability. I also made the read-aloud books in class check outs. The first reason is if I needed to replace it, I would notice that only when I was reaching for it to make a tie-in. Secondly, the scarcity created demand for it.
Immediately I might be able to create my own images which show in still images, in sequence, how Eratosthenes figured the alternate interior angles of the section of the Earth.  Of course, online I can make use of links between future ideas and the way the rays of the sun hit the Earth unevenly. I would link back to this idea especially when starting weather, where one of the first things considered is how the Earth is heated differently in differing places on the Earth’s surface – directly related to the ways the rays strike the surface. And the available videos would be beneficial to be accessible to my students more than once in class.

Prime pic from Lasky Book

Blended Learning Module for Eratosthenes

Note that while my plans for Tuesday – Friday from the link to my planbook page above ARE represented, the entire class does NOT take place in the Learning Management System (LMS). Instead this is a place to check the general flow of work, the directions, turn in work, and reference those always important images, videos. However, the learning is still taking place in our classroom!