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5th Grade Math - Calculating Volume of Rectangular Prisms

Clip 8/13: Calculating Volume of Rectangular Prisms Lesson Part 2A


As her 5th-grade students draw the strategies that they used in each act of the Three-Act Task, Mallory circulates around the groups. Students use the printed image of the first act—the closed box—annotating and drawing to indicate how their estimates were connected to what they observed. Mallory asks, “How are we going from the image that we see to the estimate you had?” She encourages students to use labels (e.g. “length = 4 sugar cubes” as opposed to “L=4”) to help others understand their thinking and their process.

Teacher Commentary

Sometimes I wish parents could be in the classroom, to see how their child presents a way to solve it and justify it, and how this other child does it, and this other child does it. There's days where they show me something, and I've never seen it before, but it is accurate, and it justifies their reasoning, and it is the most beautiful thing in the whole world. Teachers need to open that world of explaining, you know—the reality of why it's necessary to teach all these strategies and provide reasoning.

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