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Standard 2: Reason Abstractly & Quantitatively

Clip 6/13: Standard 2: Reason Abstractly & Quantitatively Using Proportions & Ratios Part 1


Mathematically proficient students bring the ability to contextualize, to pause as needed during the manipulation process in order to probe into the referents for the symbols involved.

Hillary Lewis-Wolfsen leads a re-engagement lesson on the proportions and ratios, helping students to recognize what a visual representation of a simplified fraction looks like. In this clip, she gives her students “think time” to jot down their ideas, then responds to a student with the correct answer by asking another student to explain her answer. Lewis-Wolfsen comments that her “students often understand more if they hear the explanation in a variety of ways, and not just from the teacher.”

See this video in the context of an entire lesson.

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