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 3, Quips Discuss, 1:22

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  • The teacher centers the discussion around circumference. This discussion leads students towards seeing the need for breaking up the circumference.

  • The teacher follows a student suggestion of dividing up the number of quips in a half circle by 180 degrees and the teacher follows this tangent until another student points out why this will not work. They do this by attending to the units. This will only help further the students' understanding of why they need to break up the circumference and how to do it.

  • To ensure the students are understanding what they have found, the teacher asks them what will happen if he goes 1.63 centimeters along the arc (as he uses the diagram).