Kinds of Angles

Humor warning... Be advised: this post rates zero laughs out of 5.

Last week in the 3rd grade class I taught a math lesson on angles. It was a good, hands-on lesson about the names of different kinds of angles...you remember them: right angles, acute angles, and obtuse angles. The lesson included allowing the kids to go around the classroom with an "angle finder". An angle finder is simply two 6" strips cut from index cards that are joined together with a brad at one end. This allows the kids to hold the angle finder on the edge of a desk or against the braces under a table, which helps them visualize the angle better.

I went over the names of the angles, doing the usual thing of emphasizing how angles that are smaller (less than 90 degrees) are "cute" acute angles, and then, lowering my voice I showed and named an example of an OBTUSE angle. After they had spent a few minutes looking for different angles and sharing what they found, I held up my folding/flip cell phone. This of course grabbed their attention. I slowly opened the phone and named the angle as I did so. Soon they were joining me. In high-pitched voices we said, "Acute...acute...acute...acute." Then, in a regular voice, "Right angle." Finally, in a deeper voice, "Obtuse...obtuse...obtuse...obtuse."

To finish it off I wish I had held up my open phone and written on the board "Obtuse" and "Open" and circled both O's. It would have been one more way for them to remember the name. I think they're most likely going to remember the "cute" acute angle anyway.