When children sleep better, they're healthier—mentally and physically. The state of California is now prioritizing the importance of good sleep in terms of education by mandating later school start times.

As of July 1, public high schools and middle schools will start later in the morning in an effort to combat sleep loss and help growing adolescents get the rest they need. California law SB 328 requires high schools to start no earlier than 8:30 a.m. and middle schools no earlier than 8 a.m. The law cites the academic benefits of a later school start time—something the state of New Jersey is also trying to adopt.

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Chronic sleep deprivation among teenagers is at an all-time high, according to experts. The lack of sleep within this age group has been linked to poor academic performance and mental and physical health problems, as well as substance abuse and sloppy driving. Because of these public health risks, the American Academy of Pediatrics endorses later school start times—no earlier than 8:30 a.m., as even 60 extra minutes of sleep per night can have major benefits in staving off long-term health issues.

How can later school start times improve a child's mental health?

Does your child struggle to wake up to get ready for school? Are they still sleepy in their classes, unable to concentrate, or even falling asleep during class? While frustrating, this is not an uncommon experience for adolescents in the United States.

The recommended number of hours children need to sleep depends on their age. According to the National Sleep Foundation, children ages 6–13 need between 9 and 11 hours of sleep at night. Teenagers (ages 14–17) need 8–10 hours each night. Unfortunately, most American adolescents are not getting enough sleep. Nearly 60% of middle schoolers do not get enough sleep on school nights. For high schoolers, that number is over 70%.

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Recent research has shown that in schools operating with a later start time (from 8:30 a.m. on), students not only got more sleep on average, but academic outcomes and attendance rates also improved, and car crashes involving teen drivers decreased.

An insufficient amount of sleep takes a toll on academic performance, a National Sleep Foundation poll found. The research shows that 28 percent of students reported falling asleep in school at least once a week and more than 1 in 5 fell asleep doing homework with similar frequency. 

The American Academy of Pediatrics also recommends school districts help optimize sleep in students by aiming for start times that give them the opportunity to get eight-and-a-half to nine-and-a-half hours of sleep. Since teens naturally go to bed later (no matter how parents feel about that, it's true), this makes a lot of sense in terms of prioritizing their health.

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“I’m over the moon that California has recognized the importance of science and will now put our children’s health and welfare at the forefront of the decision-making process,” said California state Sen. Anthony Portantino. “Generations of children will benefit from starting later in the morning as we know that test scores, attendance and graduation rates all improve after shifting to a later start time. As a parent, I am also pleased that depression, sports injuries, suicidal thoughts and car accidents all decline as well. This is truly a special day for kids.”