Terry Zavala says fatigue is a near-constant for a busy high school student and it affects her in different ways throughout her day.
"In the morning it gets a little bit hard because you are still in a groggy state," the Santa Rosa High School junior said of her 8 a.m. class start. "But I think I'm more tired at the end of the day."
That fatigue can be debilitating for high school students, says Education Secretary Arne Duncan, who this week renewed his push for a later start to the high school day.
"Common sense to improve student achievement that too few have implemented: let teens sleep more, start school later," Duncan wrote on Twitter Aug. 20.
Duncan followed that call this week by citing in interviews studies that say teens' brains demand more sleep to operate optimally and that a later school start for high schoolers would help students perform.
For generations, the high school day has typically started at about 8 a.m. Some high schools even offer a "zero period," an even earlier start to allow students to take an extra class during their day.
Pushing the start time from a typical 8 a.m. bell to 9 a.m. or even 10 a.m. could have what Maria Carrillo High School Principal Rand Van Dyke called a "cascading effect" on the rest of the students' day — and that or their families.
Sports schedules and other extra-curricular activities would push into the hours of darkness and students would not get home until well into the evening, some principals said.
"I think if we didn't start when we start, that kids would be getting home at such a late time they would never see their family," said Cloverdale High School Principal Theresa Burke.
Geyserville's Katherine Hadden agreed.
"It would be such a long evening for them," said Hadden, who is principal of both Geyserville High School and middle school — two schools that sometimes share athletic facilities and must coordinate practice times.
"And working around the bus schedule," she said. "We are so rural. Some kids live quite a ways out."
But principals, whether they agreed with the call for a later start time or not, said teenage fatigue is real and that administrators and teachers have different strategies for addressing it.
When creating the class schedule for the year, Hadden said she tries to avoid putting academic classes in the last slot of the day — preferring instead to book physical education, art and music at that hour.
"By then, they are kind of done," she said. "It's the seventh period teacher who kind of sees them dragging."
Late night Facebook chatting, video games or a lack of discipline aren't the culprits in students' daytime lethargy, said Dr. Leland Davis, a pediatrician with Sutter Medical Group of the Redwoods.
Teenagers have their own biorhythms that pushes their bodies to need later bed times and later waking hours, Davis said.
Remember great uncle Larry, the 80-year-old who ate dinner at 4:30 p.m. and was in bed by 7 p.m.? Teenagers have an equally strong biorhythm that pulls them in the opposite direction, Davis said.
"It's not simply a lifestyle," he said. "They are going to stay up late because they are made to do that, so if they are then made to get up, they are going to be groggy," he said. "It's not just a teenage rebellion thing."