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4th Grade Math – Classifying Triangles

Clip 11/18: Lesson: Classifying Triangles Part 2C

Overview Download Transcript (PDF)

As the fourth- grade students share their attempts at creating right isosceles triangles within a square frame, some students disagree with each other.

Hillary Lewis invites a student to explain his disagreement and his thinking. She uses questioning strategies to help him convince himself and others.

Teacher Commentary

Hillary Lewis

Here, one of the students had come up with kind of an informal proof of what he was trying to argue. It was important for him to be precise in not just his own decision-making but in being able to explain it to his peers.