What should I do about the spread of homosexuality and obscene language among the students in my class, knowing that reporting it to the administration might cause major problems given the prevalence of these phenomena among most students?

Reviling Allah is an act of disbelief and apostasy, and homosexuality is a type of sodomy. It is obligatory to condemn those who commit these abominations. If you cannot change the evil with your hand, then do so with your tongue; otherwise, do so with your heart, and that is the weakest of faith.

We advise you to strive with some of your colleagues to counsel and influence these young people. If you fear harm, then inform a trusted administrator or teacher. If you are able to transfer to another school, then do so. If not, then avoid associating with these students to safeguard yourself and your religion.