Unit Circle Manipulative by GabeHurt

Last crawled date: 3 years ago

From the attached PDF: A unit circle, similar to the one above, is printed on a piece of clear plexiglass. A spindle is affixed at the center of the unit circle. A radius like the one shown below, perhaps printed in red to distinguish it from black lines on a piece of paper, is created on a piece of clear plastic, and is made in such a way that it fits on the spindle, forming a radius that can be turned 360 degrees on the plexiglass unit circle. Individuals can place the plexiglass over any geometry work which involves finding the degrees in an angle, and use it like a protractor to measure any angle in either degrees or radians. Another piece of sheet plastic could be printed with a fully notated protractor in order to make the tool’s measurements more exacting. A Protractor and a unit circle can be combined in this way to make plain the relationship between degrees and radians which is often a source of confusion for students in advanced High School math. Additional radii can also be created and placed over the spindle as well, for use as a learning aid in Trigonometry, when discussing adding and subtracting of radians, or for the special case trigonometric ratios. Overall, the point would be to smooth the transition from the tools and methods of polar to radial geometry.
Peg board