Proponents of a later school day suggest that sleeping later improves academic performance and allows students to get a healthy amount of sleep at night. A University of Minnesota study reported that 66 percent of students slept for at least eight hours when school started at 8:55 a.m., according to Parade magazine. When school started at 7:30 a.m., only 34 percent of students received eight hours of sleep.
Waking up prematurely may interfere with kids' natural sleep cycles, increasing drowsiness and reducing mental focus at school. In a University of Pennsylvania study that surveyed 280 Philadelphia teens, 78 percent of students had trouble getting up in the morning, and many claimed they didn't feel alert during early classes and tests, according to ABC News. Teens may benefit most from waking up later because their circadian rhythms differ from those of adults, making them more likely to fall asleep after midnight, says UPENN researcher Dr. Richard Schwab.
However, many school districts and families oppose a later school day because it may complicate bus schedules and limit time for after-school activities, such as sports. Students with part-time jobs may have to work fewer hours, and many parents are challenged to adjust their work hours to avoid leaving children at home alone. Both of these factors can increase economic strain on lower-income families.