I'm editing my answer because I want to clarify something-
I read the question as:
- I have a problem studying; since I was put in this group, I can't get my studying done
- I think the solution is to get the other people in the group to work quietly, but there is no supervision, they hate me, etc
- How do I get them to be quiet?
I see that the other 2 answers to this question think (3) is the question they are answering.
I don't. I think (1) is the real problem to solve here. (2) is an imagined solution to problem (1). It's imagined because it involves changing other people's behavior in somewhat antagonistic ways.
In most cases, in my experience, this is an undesirable goal. Often it is impossible, and even in "successful" scenarios it leads to unhappiness.
Reframing the challenge in a way that:
- involves fewer people
- is really only about your needs, not about your opinions of, or the behavior of, others
is, in my experience- take that FWIW- a vastly more-likely-to-be-successful approach.
In that context- it sounds like the direction to go is to go back to the management of the school and ask for their help in finding a location for you to study quietly.
If you don't have relationships with the other people in the class, then it doesn't really matter to you how they are spending their time. You also very likely do NOT want to frame to management that you have a problem with them or that you want to control them.
As a student, that's not your job. Your job is to make yourself successful. Management's job is to provide the conditions under which you can best be successful.
In that context, my suggestion would be to respectfully approach the school manager you have the most comfortable relationship with, say that you are having trouble maintaining concentration and keeping your performance high in a noisy room, can a quiet room be found for you or some other arrangement be made.
Be clear that you have no animus for the other students in the classroom you share, you have no right, no way, and no interest in controlling them, you only that you wish for help to find you a quieter place to conduct your studies.
Good luck!