Students will be able to make sense of and critique others' reasoning about how volume grows.

By participating in a Gallery Walk and reflecting on cool and warm feedback, students will revise their work on Origami Boxes.

25 minutes

I project the requirements for students’ posters (Origami Boxes Task Card) and give students time to finalize their work, knowing that their posters must stand alone and be clearly understandable without any member of the group re-explaining or clarifying.

I task groups who finish early with determining another strategy to check their predictions for the boxes made by the 20x20 and 30x30 cm paper—sometimes, I share with them an insight that comes up from at least one group almost every year, which is to unfold the boxes and use the Pythagorean Theorem to see the exact relationship between the dimensions of the box and the dimensions of the paper.

**Gallery Walk for Posters** (5 minutes to talk about feedback, 15 minutes for Gallery Walk)

We have invested a significant amount of time developing an understanding of how the dimensions and corresponding volume of the boxes change as the dimensions of the paper size increase. For this reason, I want students to present their work and receive feedback through a S**ilent Gallery Walk**, which allows them enough time to see others’ approaches, make connections, ask questions, give feedback, and consider tangible features to incorporate into their own work.

Before we begin the Gallery Walk, I have each group send their Recorder/Reporter to get post-it notes for the group, which students will use to ask questions or give feedback (**MP3**). I expect students to use at least one post-it note for each of the other groups’ posters, which will be posted all around the classroom.

I give a small talk about feedback, telling students that may choose between giving **warm or cool feedback**, but must make it specific. I give students examples of warm and cool feedback, give them a moment to check that everyone understands in their groups, and have at least one student summarize the difference between warm and cool feedback.

Finally, before starting the Gallery Walk, I ask students, “Why is it important for us to have this discussion about feedback?” I call on students to share out about this, emphasizing the idea that if we really see ourselves as a community of learners who want to grow and push others to grow, we need to make sure that the feedback we give is **helpful and hearable**.

15 minutes

After the Gallery Walk, each group takes their poster back to their group and considers the feedback they agree with and disagree with. I give each group a reflection sheet, which they fill out as they consider the feedback. Groups then make corrections and improvements in response to the feedback they received and the other posters they have seen directly on the poster in red pen, which requires them to attend to precision in their calculations and explanations (**MP6**).

5 minutes

In Origami Box Homework, students calculate perimeters and areas of similar triangles; students also calculate surface areas and volumes of cubes, ultimately to begin thinking about ratios of similarity.