That collective groan you’re hearing across the country means it can only be one time of year. No, not election season, back to school time. Classes are starting soon, and science offers some advice just in time for the new year: skip the all night cramming sessions for tests. New research indicates that cramming doesn’t help, and students should just get some sleep instead.
Caffeine-fueled all nighters are practically a rite of passage for today’s students. Yet the study points out that these sleepless, frenzied attempts to make up for procrastination are counterproductive. Every hour of sleep lost impacts performance the next day, regardless of how rigorously the student pored over her books the night before.
In the new study, 535 high school 9th, 10th and 12th graders in Los Angeles kept a diary for 14 days that recorded how long they studied and slept, and whether or not they had any trouble understanding something in class the next day. They also reported how they performed on tests, quizes and homework. For nearly all of the students, the researchers found that, counterintuitively, more study time correlated with worse academic performance. The connection, however, rested in the amount of sleep the students got: more studying tended to equal sacrificed sleep.
The researchers point out that in 9th grade, the average adolescent sleeps 7.6 hours per night, then declines to 7.3 hours in 10th grade, 7.0 hours in 11th grade and 6.9 hours in 12th grade.
For students, the key for a successful academic career seems to be figuring out a way to keep a constant schedule. Of course, socializing, having an after school job or participating in a sports team cuts into would-be study hours, and thus into sleep. Besides “sacrificing time spent on other, less essential activities,” the researchers don’t offer much of a solution for balancing already crammed days to ensure adequate sleep. If only high school started at 10 am instead of 7:15.
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