Kids across the country are back in school. But this year, some students are getting more sleep.

A first of its kind law requires all high schools in California to start no earlier than 8:30 and an 8 am or later start for middle schools to help students get much-needed sleep.

13-year-old Robert Greenway is enjoying his new routine before school. “Last school year, it was more like get up, rush, rush, rush. Like you’re tired,” he says. Robert’s mom, Christine, says, “They’re zombies in the morning and then it’s very stressful to try to get them up.”

The American Academy of Pediatrics recommends teens get 8-10 hours of sleep. Studies show nearly 70% don’t get that, increasing their risk of depression, lower grades, obesity, and suicidal thoughts.

Dr. Satchin Panda of the Salk Institute in San Diego says, “Teenagers have a huge sleep crisis.”

Dr. Panda is a leading researcher in circadian rhythm science, conducting sleep studies across the nation. His research shows a later start time has a big impact in the classroom. “They actually learn better. Their grades improved by 4.5%, the tardiness also went down and overall teens actually felt much better about themselves,” Dr. Panda says.

This year with the later start time, Robert says, “I’ve focused like a lot more and um, I just felt more productive.”

Critics of later school start times say the change could hit school districts with administrative and operational pressures, make extra-curricular activities harder to schedule, and disrupt the schedules of working parents.

Massachusetts, New York, and New Jersey are also considering later school start times. Only about 20% of U.S. high schools start at or after 8:30 a.m., the time the AAP recommends.