WEBVTT

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Teacher: I would like for you to use these characteristics to
determine if this slide I am going to show you is an example or a

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non-example of a dilation.
Narrator: The teacher incorporates technology, displaying figures

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and asks students to use interactive clickers to vote on whether the
figures are examples or non-examples of dilations.

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Teacher: I just asked you to "Vote A" if it was an example of a
dilation or "B" if it was a non-example of a dilation, and here are

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our results. So most of you voted "B," which is a non-example. Raise
your hand if you can tell me why it's a non-example. Nicole?

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Nicole: Because the shapes are not similar.
Teacher: The shapes are not similar.

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Nicole: Because it stretches horizontally but not vertically.
Teacher: Good!

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Narrator: The teacher calls on students to explain how they use the
characteristics of dilations recorded on their Frayer Model to make

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their decisions.
Teacher: We just voted that this image is an example of a dilation.

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Now I want to know who can tell me what type of dilation this is.
Raise your hand if you can tell me. Anthony?

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Anthony: Enlargement.
Teacher: It's an enlargement. Very good, yes! And how did you know

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that?
Anthony: It's greater than one.

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Teacher: Okay, it's an enlargement because it has a scale factor
greater than one. And I see that you're looking at your Frayer Model

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and the characteristics. What about the other characteristics? Do
they apply?

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Anthony: Yes
Teacher: Tell me which ones do.

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Anthony: The figures are similar.
Teacher: The figures are similar. Good.

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Anthony: The size changed but not the shape.
Teacher: Good! That's a true statement. The size did change but not

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the shape. What else, Anthony?
Anthony: The figure doesn't rotate or flip.

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Teacher: Good. You're right. The orientation stays the same. The
figure did not rotate or flip. So those characteristics fit into as

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to why this is a dilation.
Narrator: As the class discusses, the teacher adds examples and

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non-examples to the class Frayer Model. Next, the students will work
with partners to practice creating examples and non-examples on

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their Frayer Models.