For the pyramid with a triangular base, students may forget that the triangle area formula involves dividing by 2, resulting in a base area of 6 square units. Prompt them to draw and label the base prior to calculating its area.

The purpose of this discussion is to allow students to see multiple approaches to solving these multi-step problems. Ask students to share their strategies for volume calculations. For example, for the cone, did they calculate the area of the base first, and substitute it into the formula ? Or, perhaps they wrote out and performed the calculations all at once.

Select previously identified students to share their thought process on the “working backward” cone problem. If possible, find one student who solved an equation algebraically and another who used backward reasoning rather than formally solving an equation.

The purpose of this discussion is to highlight aspects of modeling that students used during the activity. Ask previously selected students to share their strategies. Here are some questions for discussion:

• "What assumptions did you make while designing your ice sculpture?"
• "Once you found one set of dimensions, how did you go about working on the second set?"
• "Could the base be a circle? If so, how could we find the dimensions of a circle that would work?"

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Conclude the discussion by inviting 2–3 students to share a norm they identified in action. Provide this sentence frame to help students organize their thoughts in a clear, precise way:

• “I noticed our norm ‘’ in action today, and it really helped me/my group because .”

Students may not know how to get started because this problem has few constraints. Ask students to choose a shape for the base first, then to consider what information from the problem could help them choose a size for that base.