## Reflection: Checks for Understanding CORNERSTONE:Circle Ratios: Diameter to Radius; Circumference to Diameter - Section 2: Discovery

I thought it would be helpful to include the first page of the "Exploring Circumference vs Diameter" activity.  For each circle we can see that a little more than three diameters can fit across the circumference.  You can find that here.

This is a nice visual aid to go along with the questions:

1) About how many diameters are equal to the circumference?

3) If I know the diameter, how could I estimate the circumference?

4) If I know the radius, how could I estimate the circumference?

5) If I know the circumference, how could I estimate the diameter?

6) If I know the circumference, how could I estimate the radius?

If your class time is shorter than mine or you don't have time to get to the independent practice section, I think this is the perfect place to stop.  You just may need to figure out if all of the students can answer the 6 questions in either a discussion or a brief written reflection:  What did we learn about the relationship between circumference and diameter?  Describe the ratio PI.

How Does It Look?
Checks for Understanding: How Does It Look?

# CORNERSTONE:Circle Ratios: Diameter to Radius; Circumference to Diameter

Unit 6: Geometry
Lesson 6 of 37

## Big Idea: Through measurement students discover that PI is not only a mystical number, it is also a humble ratio.

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8 teachers like this lesson
Subject(s):
Math, circumference (Determining Measurements), Geometry, pi, ratio, Circumference to Diameter, 7th gra, circles, perimeter, Diameter
50 minutes

### Grant Harris

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