case 1

Worksheet 2, Clip 1, Discussion of Circumference, 1:32

In this clip the stundents are struggling to create the protractor.

Worksheet 2, Clip 2, Breaking up Circumference, 3:21

In this clip the teacher assists the students in creating their protractors by leading a discussion about making one for a given radius.

Worksheet 2, Clip 3, Quips Discuss, 1:22

In this video the teacher leads a discussion on how to find quips.

Worksheet 2, Clip 4, Changing the Radii, 1:39

In this clip the discussion turns to how things would change if their circle had a different radius.

Worksheet 2, Clip 4, Changing the Radii, 1:39

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  • The teacher encourages the students to think about how the construction of their protractors would change if their circle had a different radius. He gives them one as an example to reinforce the method they used and they discuss what would change in their method.
  • During the discussion the teacher is constantly reinforcing the relationship between angle measure and arc length.
  • At the end, the teach points out how they can think of what they have as a rate. This helps connect the trigonometry material back to one of the major themes of the course, rate.