It's not easy getting a teenager out of bed in the morning and it turns out the National Sleep Foundation says that makes sense.
Because even though teens need 9 hours of sleep, their clock is adjusting from the younger years, with those 9 hours based on staying up later and sleeping later in the morning.
That's why a study at the University of Minnesota is applauding school districts with staggered start times.
They say when little kids start at 7 or 7:30 am and high school is delayed to 8:30 or later, the older students end up with better attendance, are more alert, less moody and more likely to excel.