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4th Grade Math – Classifying Triangles

Clip 2/18: Pre-Lesson: Classifying Triangles Part 2

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Hillary Lewis and her teacher collaborators discuss their process of generating and developing the re-engagement lessons for the lesson study experience.

Hillary shares how she will connect the two experiences for the students and explains some of the redundancy required by the lesson study, saying, “Today when we start the lesson, I'm going to tell them that because you [colleagues] all weren't there last week, they're doing this for your benefit, to regenerate those definitions again.”

Teacher Commentary

Hillary Lewis

With the first lesson, we knew the MARS task was going to have them categorize triangles on their own, so we were just trying to give them some background information and to help them start thinking about how those triangles would be categorized. Their conversation went so well that when we got their papers back, I think only five students didn't nail it.

That became a problem then, a delightful problem, for the second lesson. So, how do you re-engage with a problem that they’ve already had?  

Typically, with a re-engagement lesson you're going to give them their work back to edit (or that's the way I do it). But with only five of them not nailing it, that didn't seem like the right thing to do. So, that's why we didn't do it in the second lesson.  Then, our challenge became, we need to focus on an extension.