Feb 20, 2012 6:28 PM
(NBC) - Getting teens out of bed in the morning is one of those daily rituals that is notoriously difficult, though always necessary.
But a new study published in the Eastern Economics Journal says more sleep can actually hurt your teen's grades.
Conventional wisdom says a teenager who gets more sleep would probably get better grades and do well in school.
Federal guidelines recommend nine hours every night, but that may be too much.
For high school students, seven hours is actually the optimum amount of sleep a teenager needs, according to the study conducted by BYU economics professors Eric Eide and Mark Showalter.
Eide and Showalter used data on sleep and standardized test scores that already existed.
But, unlike other studies, they allowed for the possibility that more sleep didn't always lead to better results.
"When (parents) read our study and find out that seven hours is really fine, then that makes them feel better about their teenager's sleep pattern," Eide said.
"I'm really tired a lot so I need a lot of sleep," said Anna Branson, a student at East High School.
Hannah Dawson agreed. "I probably get like ten hours of sleep. Like nine or ten."
At least one teacher has seen something different, though.
"I think that my experience is more often than not is seeing sleep deprived students with their heads on desks who look as though they need a little bit of cold water on their face," said East High teacher Rebecca Richardson.
The study also showed that the amount of sleep that led to the best grades tended to decline with age, with 16-year-olds needing less than 10-year-olds.
Eide and Showalter looked at data from over 1700 students gathered by the Panel Study of Income Dynamics-Child Development Supplement.
While students admit that they'd like more sleep, some say that ultimately they agree with study - maybe a little less is a little better.
"I feel like I perform less when I get more sleep because I become like lazy," said Daniel Ponce. "I don't want to do anything, and I got all my rest. But when I'm tired, I feel like doing something else and not get tired at all.
But there are still some skeptics among the teen experts.
"I definitely perform better if I get more sleep," said Ciera Washington. "If I get less sleep, I'm dead in the morning and I'm dreading the entire day. I definitely do better with more."