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8th Grade Math - Representing Constant Rate of Change

Clip 14/17: Rate of Change: Lesson Part 3B


Antoinette Villarin asks her students to gather together the cards that they determined were matches for each other and to record a justification for the match on their recording sheet.

She explains that they will now engage in a gallery walk, in which one of the student partners will travel with a copy of their recording sheet of matches and justifications, comparing their thinking to that of other pairs, and the other partner will stay at their table and engage in conversation with visitors from other pairs.

Antoinette charges her students to be alert for differences in thinking and to make modifications to their recording sheets if necessary. She also reminds students to be especially attentive to other groups’ approaches to matching the three cards that had partial or missing information.

Teacher Commentary

Students weren’t quite at the point yet of finalizing their thinking. Once they were, and they had cards matched with justifications, they could actually glue it down. I think gluing it down means that they've had opportunities to talk to other groups. I don't tell them the answer. In their final posters, they weren't all correct.

I think some groups probably needed a lot more time for the convincing, but we had to move on. I felt so guilty moving on at that point! But they had convinced their groupmates that what they were putting down was what they really believed was correct. For me, that's when to move on, because then it creates a discussion for the next time that we look at the work.

I always need them to have that talking time, where they traveled and at least looked at other students' work before they glued it down. There were a few students that did go back and did do a few changes. That's what I want, is this ability to think it's right and then go, venture out and see others. Then come back and say, "You know what? I think this part might be incorrect because…." I know some students do rush. Then they end up just gluing what they have. That's always hard. I always feel like I don't give them enough time for the gluing part.