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

Clip 12/19: Modeling through Geometry: Lesson Part 3B


Molly McNinch’s students engage with the example work, evaluating and discussing the thought processes of “Judi,” “Gerry,” and “Heather.”

Teacher Commentary

It is helpful to see, scanning the entire class, "Okay. Everybody's looking at the red one. What can I give them for the red one?", or, "Everybody's looking at the yellow. How can I use the yellow one?" Then I can be focusing on, "How can I best move my class as a unit?" versus, "How can I help one group, then the other, then the other?" Pushing them as a unit. I think they did a good job. There were only a few groups who didn't have much more that they needed to do to get to their solution, but overall, I think a lot of them improved a lot.