Here’s a research finding that many people will wish had been discovered when they were children: kids go to school too early in the morning and therefore are often too tired to pay attention and learn.
The recent finding is far from being new or shocking. There has been a flurry of research in recent years suggesting that schools ought to give students a few more hours of sleep, but fewer than 1 in 5 middle and high schools in this country start the school day at 8:30 or later – the time recommended by the American Academy of Pediatrics (AAP).
“Among an estimated 39,700 public middle, high, and combined schools in the United States, the average start time was 8:03 a.m. Overall, only 17.7 percent of these public schools started school at 8:30 a.m. or later,” the Centers for Disease Control and Prevention (CDC) wrote in the agency’s weekly report.
The study covered the 2011-2012 school year.
Hawaii, Mississippi and Wyoming had no schools that started at 8:30 or later, while 75% or more of schools in Alaska and North Dakota did. And according to the study, it typically takes a school district a year or more to implement changes to start times. 
“Getting enough sleep is important for students’ health, safety, and academic performance,” said Anne Wheaton, a CDC epidemiologist who led the study. “Early school start times, however, are preventing many adolescents from getting the sleep they need.” 
So, why don’t kids just go to bed earlier? According to Wheaton’s team, they simply can’t. Puberty causes kids’ biological rhythms to shift, making adolescents sleepier late at night and early in the morning. The presence of televisions, computers, and cellphones in teens’ bedrooms also contributes to poor sleep habits. And the delayed sleep patterns and early start times of most schools is leaving kids chronically sleep-deprived.
Less than a third of high school students get eight hours or more of sleep per night, which is not only bad for schooling, but also for overall health. Research shows that lack of sleep can lead to obesity, diabetes, cardiovascular issues, and more. Sleeplessness can even age your brain significantly, while getting the proper amount of sleep actually removes toxic waste from the brain.
“Adolescents who do not get enough sleep are more likely to be overweight; not engage in daily physical activity; suffer from depressive symptoms; engage in unhealthy risk behaviors such as drinking, smoking tobacco, and using illicit drugs; and perform poorly in school,” Wheaton and her colleagues wrote. 
Changing start times is a massive challenge for school districts. Montgomery County, Maryland schools found that moving high school starts by 50 minutes would cost $21 million a year. Not all parents were onboard with the idea. School bus schedules also proved to be a problem. Most districts use the same buses and drivers to get elementary and high school kids to school; the longer the buses are on the roads, the more the school district has to pay its drivers. 
This fall, Montgomery County high schools will start 20 minutes later, at 7:45, and middle schools will start at 8:15. Elementary schools will start 10 minutes later. It’s a start.
“Although 20 minutes may not be ideal for extending sleep time for all high school students, it is a move in the right direction,” said Patricia O’Neill, president of Montgomery County’s board of education, said in a statement. 
If you’re having trouble sleeping, try some cherry juice. Cherry juice has been shown to help you fall asleep faster and even extend sleep time by up to 90 minutes each night.
 NBC News