the key to staying sane/healthy, is time management, obviously. but, it's best to make sure you take the time to cool off. take breaks, even for 15 minutes. rejuvinate. sleep 7-8 hrs a night, start your homework early, and make sure you eat you three proper meals a day, and small snacks in between. eating, sleeping, and self care are the most important things in general, and they especially apply when stressing hard or working a major deadline. sometimes, granted, you'll have to all nighter, but i generally never have because i work things in time. but always always always make time to relax. downtime is crucial. worst case scenario, talk to a guidance counselor and maybe take a semester off school.