I wouldn't even let any of my students listen to music on a school computer during a test. How do I know they didn't record and email the answers to themselves, or upload it on NewGrounds lol?
That aside...You have a very rational argument, ever tried presenting it to your teacher?
Genre is an amorphous concept, what he interprets as dubstep, you could easily spin as being a (slower) drum and bass, which he has yet to forbid.
Like JK flip flop (you may learn about JK flip flops in this class btw) says, most dubstep is instrumental. If you are listening to a dubstep instrumental and you get in trouble, ask why? There are no lyrics, so how can there possibly be any offensive language, drug, sex, or violence references?
Perhaps, he doesn't like a possible subculture that is tied with dubstep (i.e. the rave scene) but as your argument infers, this is a fallacious point as drugs, sex, and/or violence is often thematic material of rock and rap music, but at the end of the day, is by no means a fair representation of the infinitely deep catalogue of the genre of music.
Even if your reasoning wins on all angles, it simply may just be a case of arbitrary "because I said so".
Stardust-Nation
Yeah, I agree. Luckily theres no such rule in my school.