Lesson #2 - Augsburg College

Lesson Objectives:
• Learn how to refer to different parts of a circle
• Discover that pi (π) is the same for all circles
Materials:
• Paper and pencil
• Ruler and yardstick
• String
• Calculator
• Compass (to draw circles with)
• Scissors (for cutting string)
Lesson #7: Circles and Pi (π)
Approximate lesson length: 1 day
Geometry: A Shapely Approach to Math
Begin by asking each student to draw a circle with their compass. Now have them look at their circles. Ask
them what different ways they can think of to measure their circle? Let them explore all the ideas they think of;
there are no wrong answers here.
Here are some examples of ways to measure circles that they might suggest:
Measure the length of the perimeter of their circle -
• This is called the circumference of a circle. In
mathematics it is denoted by the letter c. For example, if a circle has a circumference of 6, that is written
as c = 6.
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