As outlined in previous posts about sleep, this is another excellent article about the benefits of getting your required hours. Again, avoid caffeine late into the day as well as any phone/computer screens at least 1-2 hours before bed is critical. These are good habits especially for teens to start to learn early. Grinding/clenching of your teeth occurs when you do not enter a deep, rejuvenating phase of sleep (REM). Chronic clenching/grinding can cause problems with your teeth and jaw joints (TMJs).
http://www.huffingtonpost.com/2013/09/04/sleep-myelin-brain-growth-repair_n_3860316.html