This is how most of the human population is unfortunately. The good news is that later in life, you will be able to pick and chose who you associate with. Once you enter the job market, if you have a professional attitude, and a decent education, you will get jobs over these people, while they and their unplanned offspring starve. Im not trying to make you feel better. This is fact. School may seem like your whole life right now, but once you are removed from it by 10 or so years, you will realize how fast the time goes by, how hard life is for stupid people, and what is really important.
Whether your early experiences where good or bad, it only matters where you are headed in the future. If brutal torment causes you to temporarily abandon your social life and focus on school, they are doing you a favor. If you understand what you are learning but get bad grades from corrupt teachers, it doesnt matter. It only matters what you learn. It has been said that giving false praise is the most malicious thing you can do to a person. All of the students around you who are praised for bad behavior are being cursed. They are honing skills that will do them no good later on in life. Once they leave school, they are going to lack the necessary skills, and the opportunity to gain those skills will have passed them by.