Freshman year was tough for Sam Pigman. Classes at his Seattle high school began at 7:50 a.m. But Sam and his classmates felt tired during first period. “People were groggy and not super focused,” Sam says.
That changed in the fall of 2016, when Seattle officials postponed start times for public middle and high schools. They did it based on growing evidence that most teens don’t get enough sleep. Sam’s high school starts at 8:45 now. “That extra hour helped me a lot,” says Sam, who graduated in June.
Sleep is crucial for both mental and physical health, says Horacio de la Iglesia, a neuroscientist at the University of Washington. When sleeping, our brains process information and our bodies make repairs for the next day. But unlike young kids or adults, most teens don’t feel sleepy until around 11 p.m. That means it’s hard for them to get the recommended 8 to 10 hours of sleep if they have to wake up super early for school.
De la Iglesia wanted to know if the later start time helped students sleep more. He asked students like Sam to wear activity wristbands that tracked when they slept and woke up. The results were striking: Students got an average of 34 minutes more sleep per night after the time change. Their grades and attendance also improved.
De la Iglesia hopes his work will help convince more schools to start later. “We can’t change students’ biology, so we might as well change their schedule,” he says.