The teens are actually a particularly problematic period for humans in this respect, because it's a time when you have the sleep requirements of a child, but th

The teens are actually a particularly problematic period for humans in this respect, because it's a time when you have the sleep requirements of a child, but the natural bedtime of an adult. Most 8-year-olds can't easily stay up past 11. Most 13-year-olds can't easily fall asleep before 10. Both need at least 9 hours of sleep.