It was a Friday night, and Katherine Evans, a senior at Pembroke Pines Charter High, was fed up with her English teacher.

To vent her frustrations, she logged onto Facebook and started typing.

''Ms. Sarah Phelps is the worst teacher I've ever met!'' she wrote. "To those select students who have had the displeasure of having Ms. Sarah Phelps, or simply knowing her and her insane antics: Here is the place to express your feelings of hatred."

Two months later, Evans -- an honors student with no disciplinary problems -- was suspended for three days for cyberbullying and disruptive behavior, pulled out of her Advanced Placement classes and ''forced into lesser-weighted honors classes,'' according to a federal lawsuit filed on her behalf this week by the American Civil Liberties Union.

Evans, 18, of Pembroke Pines, is now a freshman at the University of Florida -- and worried that the stain on her academic record will hurt her when she applies for graduate school and jobs.

''She was suspended for cyberbullying, and that certainly sounds pretty bad," said her attorney, Matthew Bavaro. "This is something that could obviously become an issue for her."