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5th Grade Math - Calculating Volume of Rectangular Prisms

Clip 2/13: Calculating Volume of Rectangular Prisms Lesson Part 1A


Mallory immediately begins her lesson on calculating volume by introducing act one of a Three-Act Task. She says she is going to play a short video, commenting, “In this clip, I just want you to watch. I want you observing what’s in the video. After it’s done playing, I’m going to play it again.” The video itself is only a few seconds long and shows hands manipulating and showing the different sides of a box of sugar cubes. The second time she plays the video, she asks her 5th-grade students to “write down any questions you might want to ask as a mathematician. Anything that you wonder.” She elicits some of the students’ questions, and together the students and Mallory arrive at her question “How many sugar cubes are in the box?”

Teacher Commentary

This particular lesson is in the form of a Three-Act Task, where a particular picture or video is shown to the students to bring about questioning, and then bits of information are released a little bit at a time. The whole point of a Three-Act Task is to see if they’re able to reason through certain things or ask certain questions that help them solve bits of information that are needed for a problem.

Before the students even start something, or before I start talking, it’s about allowing them to (either independently or with a group or with partnering) post some questions or try to tackle the task with a little bit of wonder and observation. That opens up this unique shift when you take time to do that small snippet of wondering observations. “What do you think is going to happen?”

Materials & Artifacts