PANAMA CITY, Fla. (CBS Local) — The mother of a high school student in Florida is calling for disciplinary action against a teacher who wrote “WTF” — shorthand for “what the f***” — at the top of her son’s homework assignment.

Melinda Smith said she was surprised and upset when her son handed her his science homework and “WTF is this? Absolutely no credit” was written in red across the top.

“It wasn’t anything about not getting the credit, it was more so the language, about what they’re writing to a student. That was very inappropriate and not acceptable for a teacher whatsoever,” she told WJHG.

Smith is calling for the teacher to be held accountable.

“I think for sure she needs to be reprimanded. I believe that something should be placed in her file,” Smith said.

Coy Pilson, the principal of Rutherford High School in Panama City, said district officials are investigating the incident but it is unclear if any action will take taken against the teacher.

Pilson has not disclosed the teacher’s name but said “she was apologetic” and acknowledge the note “was a mistake on her part.”