Encourage your teens to get eight hours of sleep each night.
Most teens are likely to get less sleep, not more, than they did when they were younger. Teens do best on at least eight hours of sleep. But schoolwork and social life mean that too often, they get six hours or fewer. This usually happens on school nights when they need sleep the most.
Tired teens may have less interest in school. They may be moody and depressed. They may fall asleep at the wrong times, such as in class.
Tired teens may also try to "catch up" on sleep during the weekends. This is difficult on their bodies and may negatively affect the schedule of everyone else in their households.
To keep distractions to a minimum and help your teens get the sleep they need to do their best in school, establish family "quiet times" after a certain hour. This will help ensure your teens are getting at least eight hours of sleep.
Source: The Parent Institute