Sleep changes among teens are related to shifts in their circadian rhythms at the onset of puberty. Most tweens and teens experience what is considered a delayed sleep phase as the result of swift and complex changes to the adolescent brain which are associated with its final development. They are often described, in fact, as “night owls.” This means their rhythms undergo a slight biological reset that makes it more natural for them to abide a later schedule.While most younger children and adults may more naturally feel sleepy between 9 and 10pm, teens are far less likely to feel sleepy until at least 11pm. For some, the rhythms shift as late as 1am. These changes are hormonally related and have little to do with poor self management.