The American Academy of Pediatrics (AAP), which has called for later school start times since 2014, recommends that middle and high schools start no earlier than 8:30 a.m. But until recently, there’s been a patchwork approach to meeting that recommendation. The result: While various districts, cities, and counties have opted to make changes, the majority of middle and high schools still start too early. These start times make it nearly impossible for teens, whose body clock tends to shift to a later schedule at the onset of puberty, to get the eight to 10 hours of sleep recommended for their health and well-being.

That’s about to change in California, when a law—the first of its kind in the nation—goes into effect on July 1 requiring the state’s public high schools to start no earlier than 8:30 a.m., and its middle schools no earlier than 8 a.m. Both New York and New Jersey also have similar bills under consideration.

Click the link in the paragraph up top … and find out why this is considered a progressive change.