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

Clip 9/19: Modeling through Geometry: Lesson Part 2B


As her students use physical objects and a [roll radius calculator]( to test their ideas for possible inclusion on their group status posters, Molly McNinch circulates among the groups, asking them to consider different quantities and engage each other in a discussion of their ideas.

Teacher Commentary

In order to do work well in groups, the students need to know each other and be able to collaborate. In the beginning of the school year, they’re still trying to meet each other, and so those little tiny breaks in teaching where it's like, "Oh I have to go put this thing up on the smart board," or "Oh, I forgot to take roll," instead of letting that be dead time I say, "All right, so you guys are sitting with three new people." Any time I change seats even now I say, "Okay, you guys have 30 seconds. Find out what everybody at your table's favorite color is." Or something just super random where they have to find out something. Then the next few questions that I ask I say, "Okay, let's solve this problem." I use my cards and I'll say, "Okay, Lesley. Tell me the person to your left's favorite color, and then tell me this." So it holds them accountable, too because Lesley needs to know what Danny's favorite color is. I think just those little things force them to talk to each other and hold them accountable. It's like now I have to figure out everyone's favorite color, but you get to introduce yourself and get to know each other. I’m constantly trying to find ways for the students to feel at ease in the classroom. If the classroom is a safe place for students, then they feel comfortable learning AND making mistakes. Never underestimate the impact of your classroom culture.