## Reflection: Discourse and Questioning Verifying Properties of Dilations - Section 2: Making Predictions

After teaching this lesson, I believe that I could have students read the words of the properties of dilations 10 times, and many still wouldn't fully understand them.

The words "A dilation takes a line not passing through the center of dilation to a parallel line and leaves a line passing through the center unchanged" just doesn't resonate with a lot of students.  The same is probably true for the words "The dilation of a line segment is longer or shorter in the ratio of the scale factor"

However, when we got to the part in this section of the lesson where students had to relate the properties to an actual diagram and make predictions, I saw it become real for the students.

This reminded me that students will often not fully understand things until they are forced to confront the incompleteness of their understanding. It's not that students are stubborn or that they're unmotivated, it's that they don't know what they don't know until they are put in a situation that exposes a their need to deepen their understanding.

I take away from this that I need to always be looking for those higher order depth of knowledge (DOK) questions and problems that will confront students with their need to develop their skills and understanding.

Reading Math is Different and Needs to be Taught
Discourse and Questioning: Reading Math is Different and Needs to be Taught

# Verifying Properties of Dilations

Unit 6: Similarity
Lesson 2 of 8

## Big Idea: Conceptions vs. Reality....Let's see how student predictions stack up against the properties of dilations.

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Standards:
Subject(s):
Math, dilation, geometric similarity, properties of transformations, verify properties of dilations
55 minutes

### Anthony Carruthers

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