# Lesson Part 4D

## lesson part 4d

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Molly McNinch asks her students to tape their posters up on the wall, and then engage in a “gallery walk,” encouraging them to “find one thing about one of the posters that you did not have on yours.” After Molly’s students examine their colleagues’ work, she asks them to identify strong elements in other posters, explaining the strategies that were used. Some students praise the labeling (e.g., a key) that other groups used. Other students identify the use of multiple shapes (not just cups, but cones, triangles). To close the lesson, Molly draws the whole group back together and asks them to return their materials and laptops to their places.

## lesson part 4d

9th Grade Math - Modeling through Geometry: Circumference of a Cup’s Roll
Molly McNinch, San Lorenzo Unified School District, Woodside High School, Woodside, California

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STUDENT: That's R minus S.

MOLLY MCNINCH: Less than a minute. Let's get them on the board please! Three, two, one ... All right, find a seat, you guys. All right, so ... All right, Julian, find your seat. Please. So, for those of you guys who have all finished your posters ... Now, we are going to get out of our seats when I say go, and I want you guys to find one thing about one of the posters that you did not have on yours. Okay? So, there's one, two, three, four, five, six posters that are going to be put up. All right, everybody gets up. You all have Airheads [education technology] except that group who I haven't given them to. So, walk around. One thing you notice. Okay, go.

One thing you notice. So, Julian, the posters are right behind you. Okay. All right. There we go. Okay. All right. Now. Okay. Now once you have your thing that you notice that was really cool, you can go back to your seat. So once you found the thing that you thought was super cool, you can head back to your seat.

Okay. All right. Now, I would like to hear one -- oh sorry, I want to hear two things, two things. All right, so who saw something that was really cool that they didn't have on their poster? Gavin, and then we'll do Kelsey.

STUDENT: The final equation.

MOLLY MCNINCH: The what?

STUDENT: Final equation.

MOLLY MCNINCH: On whose poster?

STUDENT: On Jack's poster.

MOLLY MCNINCH: This one?

STUDENT: Yeah.

MOLLY MCNINCH: So having Heather's equation and going all the way down to their final equation. So, some of the -- yeah, it's really nice. I like this diagram. Really great. Yeah, so again, we're not focusing on getting all the way to the end. We're focusing on what strategies were used.

So Kelsey, what were you going to say?

STUDENT: I liked on Veronica and Robert's poster. They had a key and some diagrams. MOLLY MCNINCH: Mm-hmm [affirmative], yeah. A key's always really helpful. What is also helpful is those diagrams. I like that. And then Cole, you want to share with us what you were going to say?

STUDENT: I forgot.

MOLLY MCNINCH: Okay, he forgot. All right. Does anybody else have something they want to share? Yes? No? Caroline?

STUDENT: For, like, the top -- like, some people did the triangle like in Veronica's. I didn't like really think of that.

MOLLY MCNINCH: Yeah, so a lot of people -- this was also in third period, as well. So some people came up with these great diagrams of cones or triangles, and some people only had their cups [Inaudible -- bell rings], which is really great.

Now, please -- red, blue, yellow paper, put them back in the sheet protector.

Chromebooks go back in the box. If you borrowed markers put them back, and if you haven't gotten an Airhead, I'm coming to you, Max and Nathan.

I think that having a slightly larger group, focusing them to make a poster, focusing them to put all of their work in one place, allowed me to tell them to focus on the process that they were doing versus the solution. Groups of three are ideal here. Groups of four can be too big, and it is a difficult concept for two partners to focus on individually.

Instead of anticipating the misconceptions as, "Well, I think they're going to have trouble with the diameter and radius," which none of them had trouble with, it worked better to anticipate those needs as, "It might be best to put them in larger groups. It might be best to … change what they're producing just so that it's more familiar to them."