Discovery Based Learning

1.  Visualizing Radian Measure -- Click here to link to Ted Coe's Unwrapping A Circle Applet [T], [V]

This is a tool to help students envision the meaning of "radian" by thinking in terms of radius-lengths.

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2.  Radians and Degrees [V], [C]

The purpose of this activity is to help students visualize the meaning of a radian.

Materials:

• Copy of the worksheet:  Click here to download
• Pipecleaner or a string
• Scissors

Alternative:  You can have students check their answers to Part (b) by cutting a string or pipe cleaner rod to the length of the number of radii they determine and wrapping it around the circle to see if the length is correct.

Students should come to realize that no matter the length of the radius of a circle, there are exactly 2π radii around the circumference of any circle. Thus an angle that cuts off an arc equal in length to the radius of a circle will have the same measure no matter the length of the radius of the circle. The measure of such an angle is one radian.

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3.  Radian Explorer -- Tools For Teachers (you will need a user name and password) [T], [V]

Click here to follow along in a Discovery Based Learning Activity