Teenagers have been nearly impossible to drag out of bed on school mornings for decades — and now it appears there might be method in their madness.
A new study conducted by the University of California has shown that students learn better if classes start later in the morning.
Delaying the first class by just 50 minutes can result in dramatic improvements in performance and the effects last for the rest of the school day.
"The most interesting finding was that the effect lingered throughout the day," study leader Teny Maghakian said.
"It's not just that you do poorly in your first-period class then wake up and do well in the rest of your classes; having an early-morning class negatively affects your performance throughout the day."
The study, published in the American Economic Journal is the largest of its kind. It observed more than 6100 students over a four-year period and found that starting lessons at 9am or earlier resulted in significantly poorer learning.
This is thought to be due to teenagers' circadian rhythms. While adults sleep most soundly at 4am, teenagers' bodies keep producing sleep hormones until 7am.
This means that waking a teenager at 7am is the equivalent of waking an adult at 4am.
Australian schools have been debating pushing back school start times to 10am in a bid to decrease absenteeism and allow students to catch up on sleep.
Later start times have also been suggested as a method of easing traffic and public transport demand in peak hour.
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