BURLINGTON, N.J. (WPVI) -- Calls to start school later for teens are being heard in one South Jersey school district.
Burlington City schools are pushing back start times for most grades with the 2018-2019 school year.
Beginning in September, the day's first session in 7th through 12th grades at the high school will start at 8 a.m., 20 minutes later than the current start time.
In the third through sixth grades at the Wilbur Watts Intermediate School, students will start their day at 8:05 a.m., five minutes later than now.
There will be no change in times at three elementary schools for preschoolers through second-graders. Their day begins at 8:25 a.m.
In a letter sent to parents last month, Superintendent Patricia Doloughty made it clear science was pushing the change.
"There is extensive research that finds that teenagers are getting too little sleep, and later school start times improve student learning outcomes," said the letter.
That research also shows that teens' biological clocks shift later, making them unable to fall asleep or wake as early as younger children.
Studies show teens learn and function better with later school start times.
The district acknowledges that the old 7:35 a.m. start time was a little too early.
in 2014, the Academy of Pediatrics recommended that high schools not start till 8:30 a.m., so that teens would be able to get the 8 1/2 to 9 1/2 hours of sleep their bodies need.
The National Sleep Foundation says most teens now get about 7 hours of sleep.
The letter also went out to families in the Edgewater Park District, because their high school students attend Burlington City High.
School officials also hope the later start time will improve safety for students who walk to school
High school principal James Flynn hopes the change will also allow extra daylight and safety for students who walk to school, especially during the dark winter months.
Some of them have to cross busy Route 130.
Dismissal times at Burlington City High School aren't changing, even though classes will start later.
Instead, the lunch period will be eight minutes shorter, and class periods will shorten from 55 to 53 minutes.
School officials didn't rule out lengthening the school day later, if they feel students aren't getting enough instructional or extra-curricular time.
The Watts' dismissal time will be moved back five minutes to adjust for the start time change.
On top of the health benefits, a RAND Corporation report earlier this year said later school start times would mean fewer car accidents, and an overall major boost to the economy.
Schools have resisted the change, saying it would be too expensive to re-schedule buses.