Why School Days Need To Start Later

No one enjoys being dragged from their bed and thrusted into the waking world before they've had enough sleep. For teenagers, however, an early wakeup is more than a nuisance. There actually are biological reasons as to why they should stay in bed longer -- and why schools need later starting times to avoid harming their development. A wealth of research going back to the 1990s has demonstrated how early school starts are incompatible with adolescent biology. Teenagers sleep differently: most need at least 8-10 hours a night, and changes to their circadian rhythm (or inner clock) during puberty mean they tend to get tired later in the evening.