Need more zzzzzzzs

It is a myth that teens need less sleep than young children. They need 9 to 10 hours a night, although most fall short. Part of the problem is a shift in circadian rhythms during adolescence: It makes sense to teen bodies to get up later and stay up later, Johnson said.
But due to early bussing and class schedules, many teens rack up sleep debt and "become increasingly cognitively impaired across the week," Johnson said. Sleep-deprivation only exacerbates moodiness and cloudy decision-making. And sleep is thought to aid the critical reorganization of the teen brain.
"There is a disconnect between teen bodies and our schedules," Johnson said.