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9th Grade Math - Modeling through Geometry: Circumference of a Cup’s Roll

Clip 3/19: Modeling through Geometry: Pre-Lesson Part 3


In their pre-lesson conversation, Molly McNinch is asked by her math colleague Jim Karditzas to describe how the documented lesson fits into her larger unit of study. Molly responds that the larger unit focuses on tessellations and transformations, and the class had just completed a previous unit on similarity.

Teacher Commentary

Some students will have struggles identifying similarity over congruence. And justifying what makes it similar versus what makes it congruent.