What to do when some students pay someone to solve their exams projects and thesis? There are some students on my masters program in mathematics who don't even know the basics of mathematics like an example of a continuous function or similar. They pay someone else to solve the problem sheets and projects for them and somehow managed to pass exams by learning by heart only past exams. Of course I don't have a proof for any of this but I know since they have told me. The head of school thinks he is doing a good thing and that all of the students who passed exams are good students, while myself and students like me were put in a very unfair position. Would there be any sense of addressing this thing and how? For the thing to be worse, those students are female students from the rich Gulf countries and they and their husbands do not need to work(I have absolutely nothing against that, but situation might be politically and religiously complicated in case of addressing this problem. Of course, these kind of things happen in case of any other countries/religions as well, but this is the situation in my case). Just for the sake of argument, in my case, I had to work full time while studying full time. Any advise would be appreciated. Thanks.

EDIT:
I am unable to comment so will answer here. The projects and problem sheets took a part in a scoring of the final grade. As they have told me they have been studying only one semester material (out of 2 semester material) and have been learning solutions from the old exam papers from the previous years and many of the questions have been repeated. 
Also we just had to send the paper via email or give it in a paper form, without any reporting or discussion. 

EDIT: in reply to comments, @scaaahu asked: "My point is the student does not even know the basics. How useful would the old exam papers be?" Well, it can be if you are learning without any understanding and by heart from the old exams.

EDIT: It would be impossible for the head of school not to know what is going on, he is well aware of them and the situation but still does not want to do anything about it.

EDIT: I did not mention that their English language proficiency almost does not exist and they presented papers with a great English and professional maths.
I will take a wild guess and speculate that the university referred to in the question is in a country that has high levels of systemic corruption, as measured for example by Transparency International's Corruption Perceptions Index. Countries near the bottom of this ranking have the feature that most if not all of their main institutions experience high levels of dishonesty and unethical behavior. That sounds consistent with the OP's description, and conversely, in countries that rank low for corruption it is hard for me to imagine an academic environment where such rampant large-scale dishonesty could be practiced with impunity by so many people and tolerated and ignored by so many others.

Assuming this premise, I find it helpful to reframe the question as a broader and more general one, that would contain the OP's question as a special case:


  What should I do if I am an honest, hardworking person who wants to learn a trade, get an honest job, be judged for my abilities and become successful thorugh talent and hard work; but I live in a country with such high levels of corruption and dishonesty, and such dysfunctional institutions, that I see people all around me getting ahead through cheating and other dishonest means, leaving me no practical way to realize my dreams in the honest way I wish to?
  
  Should I try to fight this behavior? Should I try to find a rare honest person around me in a position of power to complain to about the dishonesty I observe? Will this change anything?


My answer is probably not a very helpful one, but I think it is the only realistic one: leave. The forces you are trying to fight are so much bigger and more powerful than you, that unless you are willing to dedicate your entire life to fighting them, knowing that you will achieve either nothing or very little, your only other choice would be to keep your head down, either ignore or join in the cheating, and resign yourself to a life of dissatisfaction and unfulfilled dreams.

Sorry it's pessimistic and depressing, but there it is. I would probably vote this answer down myself if I could. :-(