I reckon software licensing is the only potential stumbling block in terms of cad cam.
The basic G code programming we learned in 3rd year fitting focused on math of late yr9 to early yr10 difficulty. (I failed maths so it was a good catch up!)
I would reckon it should tie into math and science, it would certainly spice up mathematics. Algebraic expression really lost me at school, seeing math put into practice could alter the paths of a lot of school kids.
A discussion with TAFE staff could have your hands on their 3rd year study books (lost mine 8 years ago) which you could slice it down to raw format.
We focussed mainly on G41/42 offset and the trigonometry involved in polar co-ordinate calculation sin,cos,tan. The grand finale was a helical interpolation which was quite a mind bender the first time around.
Calculating speed and feed were pi type calculations, pretty straight forward.
Cad cam is a whole other activity which could tie into graphics class because it pretty much involves learning cad. Kids are so computer savy these days, maybe it would be a snap for them, I'm no einstein.