Sleep For Teenagers: The Science Behind A Good Night’s Rest

Research suggests that too little sleep is related to inattentive behavior, poorer school performance, negative mood, daytime sleepiness, increased risk-taking behavior and increased risk of driving accidents. Some studies have shown that when you let teens sleep longer in the morning, they are more alert, attentive and feel better and that this has positive consequences for school attendance and performance. 
http://www.texaschildrensblog.org/2012/10/sleep-for-teenagers-the-science-behind-a-good-nights-rest/ 

Teenager sleeping in classroom at desk