School Start Time Matters

Early start times cause sleep deprivation in teens

Sleep experts have identified a shift in sleep cycles that makes it difficult for most adolescents to fall asleep as early as younger children or older adults. Typical sleep cycles begin around 11 p.m. for teenagers and continue through 8 a.m. Thus, an early school start time directly prevents adolescents from getting the 9 hours of sleep that they need and forces them to wake up in the middle of a deep sleep.  Kids forced to wake up too early aren’t just getting too few hours of sleep – they also miss out on REM sleep, which is important for consolidating memories and helping people to remember what they learned that day. REM sleep tends to be concentrated in the last third of the night, or between 6 a.m. and 9 a.m. for a typical teen.

Why should parents worry about sleep deprivation?

Sleep deprivation has been shown to impair creativity, abstract thinking, problem-solving, innovation, concentration, attention, decision-making, coordination, and motor response times. It can cause irritability, moodiness, emotional instability, aggressiveness and stress. Insufficient sleep reduces the body's response to immunization and its natural ability to fight off infections. Sleep is a powerful regulator of appetite, energy use and weight control. Lack of sleep contributes to factors associated with heart disease and stroke. Sleep deprivation increases the likelihood of stimulant and alcohol use. Sleep deprivation magnifies alcohol's effects on the body, increasing impairment of cognitive abilities and motor coordination. 

Our school schedule works against adolescent sleep biology

“Sending kids to school at 7 a.m. is the equivalent of sending an adult to work at 4 in the morning. It’s almost abusive to them.” —William Dement, M.D., Sc.D., Ph.D., Professor of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Division Chief, Stanford University Division of Sleep.