If we’re going to focus on special triangles, might as well really focus on special triangles, right?
Rather than having kids label the “special” angles (multiples of 30 and 45 degrees) on a unit circle, I made up cardstock special triangles that matched the protractor-grid trig reference sheets. Students labelled the side lengths with a hypotenuse of 1, and can then physically move them around on the unit circle as a reference.
Here’s the printable PDF. It should be the correct scale to match the printable sheet in the previous post (ie. the hypotenuse will match the radius of the printed circle).
My class is a mix of students of different ages, many of which have taken this course before and some of which have taken the previous Principles 11 or 12, which had less of a deliberate focus on the special triangles. So I haven’t pushed hard for everyone to use these, but a lot of the students have picked up on it and pull out the triangles to check solutions on quizzes or homework.