“Despite decades of research, thousands of publications and clear science, schools in only a few states and the District of Columbia have pushed their start times to 8:30 A.M. on average, which researchers say is a compromise.”
Teens need about nine hours of sleep and get closer to seven. Their body clocks shift by a couple of hours at puberty, so an earlier bedtime does nothing. The CDC endorses later starts and California already made the switch. Everyone else keeps waking 15-year-olds at 6 A.M. because the bus schedule outranks the science.