Weeks ago, I told the seniors that knowing the function values on the unit circle would be helpful when we got to the next section on graphing the trig functions. Too many of them didn’t believe me. Now some of them can’t tell the difference between the graphs of sine and cosine.
I spoke to my mentor about the situation. His suggestion was to give a daily unit circle quiz, all or nothing. Lose a negative sign? Too bad, no credit. This continues every day until the entire class gets it right.
I told them about it on Monday. Our first quiz was yesterday. Yesterday’s results? 46% got it. Today? 82%.
Prior to this we had cut out the special triangles and moved them around the unit circle. We filled out a chart of all six function values from 0° to 360° ( or from 0 to 2π, take your pick). We talked about the patterns. We’ve drawn triangle after triangle in the circle. That didn’t seem to matter for some of them. I’m dismayed that it took such drastic measures for them to learn the function values. I’m not sure if they’re able to apply them to anything yet. We’ve spent the last two days in the lab, working on a Sketchpad investigation of transformations.
Now, if they had only believed me last semester about needing to understand the the
affect effect of 2f(x) + 1. “But Mrs. B, we thought you were kidding when you said this stuff would come back…”