Could really do with some words of advice and encouragement - feeling really upset and helpless. Sorry its a bit long.

My ds is passionate about acting, has lots of experience of performing, mostly on stage, but also film and radio. He is bright, hard working, polite, pleasant and keen, talented. His dream was to study acting on a 2 yr BTEC and then go to drama school or uni to do an acting degree.
In Sept he started college, and he was so excited about going.Things were good to start with, but 6 months into the course he has found it hard - not with the work (at parents evening they said if they had a class of students like my ds they wouldn't need a teacher!) , but with the attitude of 2/3 rds of the class. Many don't take their art seriously, they mess around in class, don't learn lines, are rude to the teachers, and worst of all, make my son feel left out because he works hard and is happy to contribute intelligently in class and doesn't spend all his time going on about getting drunk etc.
Whilst rehearsing ds asked another student if he could check his line by looking at their script ( someone them are not off book till the last minute) they told him to F*** off and get his own. Last week one of the students (considered to be the 'alpha male' of the group) spent the day winding up the teacher (teacher, who is an actor, only does 1 days teaching a week and isn't popular) to the point where the student refused to do the activity, called the teacher a twat and stormed out. The HOD of dept had a word with the student, and the whole class and returned the student to class. I asked DS this week what had happened about it and apparently nothing, except this student's status has rocketed for standing up to the teacher and now he is a hero, about he still continues being disruptive.
I did speak to the form tutor about my concerns re behaviour in class and attitudes last term. The advice was for ds to be less keen and not answer question is class. So now ds stays quiet in class & no one answers the questions...
I feel so sad and disappointed that so many of the class seem to see this course as nothing more than a laugh and just something to do rather than working in Tescos. Disappointed that the teachers just accept it as normal. I don't know what to do.
Ds is coping with it all better than me. He enjoys the productions, but says the rehearsal are uncomfortable because of the general attitude. He says he will just keep his head down, plod on with the course and enjoy his other drama stuff. He spent last weekend doing a NYT course,and will do next weekend on it too. He was on such a high when he got home last weekend it made me realise how down he is when he's at college. It just doesn't seem fair.
So, should he just accept this, is this how life is? He is not learning much where he is, and he certainly isn't happy. Should I encourage him to leave and do A levels instead somewhere else whilst he is still entitled to free f/t education, and then go on to follow his passion at 19 and do a degree. I could go and talk to the teachers, but it all seems so futile, nothing is likely to change.
Am I just expecting too much?
Thanks for reading.
Tikka