Does the Time School Starts Affect Student Performance?

High schools in North America and the United Kingdom have found that starting school even one hour later can significantly affect students' performance. This is because most teenage students are seriously sleep deprived — teens need at least nine hours of sleep a night to function properly, but most students get about six hours. Schools that have experimented with later start times typically have better attendance and better student performance, and students report being less depressed.

More facts about student performance:

• Teenagers have a unique sleep cycle. Unlike adults or children, teenagers' bodies typically release melatonin, the hormone needed for sleep, about 11 p.m. This makes them naturally fall asleep later and get up later. In high schools in the United States, about 20 percent of students fall asleep in classes on any given day.


• A school in Britain that tried opening at 10 a.m. found that persistent absenteeism dropped by almost 30 percent, and a school in Toronto that used a similar system found that its 11th-grade math failure rate dropped from 45 percent to 17 percent.


• Parents report being pleased with later start times, too, because more sleep can help regulate teens' moods. Chronic sleep deprivation, like that faced by many teens, is associated with elevated levels of depression, irritability and decreased motivation.