"There may be other factors involved, such as personality traits, that link Facebook use and lower grades," she said. "It may be that if it wasn’t for Facebook, some students would still find other ways to avoid studying, and would still get lower grades.
"But perhaps the lower GPAs could actually be because students are spending too much time socializing online."
Karpinski said it was particularly significant that graduate students who use Facebook had lower grades. Those students typically have GPAs above 3.5, so the fact that even they had lower grades and spent less time studying was a significant finding.
Because of the popularity of Facebook, it's important for universities to understand its impact on students, Karpinski said. As to herself, she doesn't have a Facebook account.
"For me, I think Facebook is a huge distraction," she said.
Facebook's popularity continues to grow. The site last week said it had signed up its 200 millionth user. Facebook's closest rival, MySpace, has about 160 million members, according to ComScore.
Karpinski and co-author Adam Duerstein of Ohio Dominican University are scheduled to present their findings Thursday at the annual meeting of the American Education Research Association in San Diego.
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