“There are always some students who can’t get the motor running,” says Gregory Downs, an instructor at DePaul University and former high school teacher. “Some of them have been up until one in the morning, and they struggle to be alert. Others go to sleep at a normal hour but need 10 or 12 hours because they’re growing so much. Still others try to go to bed early but can’t fall asleep for hours.”
High school teachers know that, for whatever reason, many of their students just don’t seem to function well in the first hours of the school day. In fact, mounting scientific evidence suggests that older adolescents are fundamentally not getting enough sleep. But why? Is it because they just stay up too late? Brain research suggests instead that these sleepy heads are actually functioning on an a time clock out of synch with adults. Thus, high school age kids may need a schedule of their own.
“Research has shown that probably the most sensitive domain to sleep deprivation is related to cognitive and attention skills.”
Kyla Wahlstrom, a researcher at the University of Minnesota’s Center for Applied Research and Educational Improvement, argues that adolescents “need increasing amounts of sleep.” As children move through the teen years, she says, they need at least nine hours of sleep a night in order “to avoid behaviors associated with sleep deprivation.”
According to Wahlstom’s research, 20 percent of all high school students fall asleep in school and over 50 percent of students report being most alert after 3:00 pm. Which means that for many kids, most of the school day is a sleepy blur. “Students who evidence a sleep lag syndrome correspond to those having poorer grades,” says Wahlstom.
“Research has shown that probably the most sensitive domain to sleep deprivation is related to cognitive and attention skills,” says Tel Aviv University professor of psychology Avi Sadeh. “At least for those who want to be good students, an extra hour of sleep may sometimes be much more important than an extra hour of study, let alone an hour of TV or surfing the Internet.”
“Teens in the U.S try to do it all, much like their parents.”
“Teens in the U.S try to do it all, much like their parents,” says Mary Carskadon, Brown University professor of psychiatry and human behavior. “In addition to school, they have jobs, often 20 or more hours a week, extracurricular or volunteer activities, athletics, and school work. Sleep? What’s that?”
Sleep patterns are tied to the output of melatonin, a hormone secreted by the pineal gland and controlled by the body’s internal timepiece, or circadian clock. High levels of melatonin produces sleepiness; low levels of the hormone make one feel awake. Through research on the interaction of circadian rhythms and melatonin, Carskadon has found that the natural sleep patterns of adolescents differ from adults.
“One ordinarily experiences sleep pressure to be greatest at bedtime and least on waking up,” she writes. But in her research, she has found that adolescents have different patterns: “The circadian pressure to sleep—regardless of how long an individual has been awake—was greatest right as the melatonin secretion was about to turn off, about an hour before ‘normal’ waking up time,” she writes. “The circadian pressure to stay awake was greatest right before melatonin secretion was about to begin, about an hour before ‘normal’ bedtime.”
Basically, this boils down to the notion that when all the adults are waking up and getting ready to go to work, high school kids are just getting down to serious sleep. This is why a number of researchers and educators has begun to advocate later start times for schools.
Just Five More Minutes
Minnesota was the first state in which major school districts implemented later high school start-times. But according to Wahlstrom and her colleague Patricia Kubow, who studied the response to the switch, teachers had mixed feelings about its effectiveness. While slightly more than half of the teachers “agreed or strongly agreed that they saw fewer students sleeping at their desks,” there was nothing close to consensus in response to the questionnaire statement: “I see improved student behavior in general.” Moreover, the change in start times complicated the timing of extracurricular activities, which concerned a number of parents, teachers, and coaches.
At Edina High School, located in a suburb of Minneapolis, which five years ago moved back the start of its day from 7:30 am to 8:30 am, the response has been generally more positive. “We have found fewer instances of tardiness and absences from first hour, more awake students, continued high levels of participation in after school activities, and no complaints from parents, students or staff,” says Laura Tueting Nelson, E.H.S.’s communications director. There is also some indication, says Nelson, that there has been “a slight grade improvement in norm referenced tests” at Edina.
There are certainly skeptics to delaying high school start time, but understanding more about how the adolescent brain works—and sleeps—can go a long way toward knowing when students are paying attention and learning, and when they’re nodding off.