Please find some adult at your school who will listen and be compassionate. There has to be someone. Talk to the principal, an assistant principal, school nurse, or teacher. You need someone else on your side, even if they are not able to convince your parents to change their ridiculous expectations. As others have said, that amount of sleep is very unhealthy, especially when you are dealing with symptoms of depression. Can you show them some research on sleep in teenagers? They will not like the effect of sleep deprivation on your mental health and then your lower grades. Could you ask one of your parents to take you to a doctor as someone else suggested? If they say no, you could lie and say it is so the doctor will prescribe a medication to help you stay awake longer. Then, when you are talking to the doctor, he/she can hopefully talk some sense into your parents. Hang in there. You will be free of them one day and able to live your life without that unhealthy control.