In our curriculum, students learn all about right angle trig and sine and cosine laws in grade 10. In grade 11 they learn about the graphs of trig functions, all done in degrees. In grade 12 they are introduced to radian measure. I was introduced to this by Tom Seidenberg, so I give full credit to him as this may be straight from their materials. I like the way it sets up what 1 radian is and gives a context to arc length over radius.
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