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9th Grade Math - Modeling through Geometry: Circumference of a Cup’s Roll

Clip 14/19: Modeling through Geometry: Lesson Part 4A


As they move toward the end of the lesson, Molly McNinch reminds her students to represent their thinking on their status posters: “What was your journey. What thinking did you do? Did you come up with a solution?” Students work to prepare their posters for sharing.

Teacher Commentary

A lot of students grasped that concept of modeling, because I think modeling, so many students will think "picture," and I liked that there were still some posters that had no images at all. I think by advancing that student thinking through encouraging the modeling of actually manipulating equations and manipulating the proportions and ratios, that's helpful. I think with regard to, "How did it advance them with modeling as diagrams?," I think by pushing their thinking towards seeing the triangles, that was a big jumping off point/hint for them. Once they saw that diagram, a lot of them, it just clicked.