How much sleep do you get each night?

A good night's sleep may be your best way to improve your performance at school. 8 1/2 to 10 hours a night is what most teens need to function well.

http://voices.washingtonpost.com/answer-sheet/daniel-willingham/how-can-parents-help-teachers.html?wprss=answer-sheet

"In adolescents, poor sleep quality is associated with depression, anxiety, inattention, conduct problems, drug and alcohol abuse and impaired cognitive function."

http://www.examiner.com/healthy-living-in-new-orleans/teen-depression-and-suicide-risk-linked-to-late-bedtimes-and-chronic-sleep-deprivation

"A report from the Jan. 1, 2010 issue of the journal Sleep found a surprising link between the typically late bedtimes of teenagers and teen depression and suicide."

What keeps you from getting 8 to 10 hours per night?