The Pace East Program at Independent Hill School was placed in lockdown after a teenager claimed he had a gun, Prince William County Police said.
The 15-year-old Woodbridge male is now charged with threats of bodily harm, police said.
Police responded on Wednesday at 8:23 a.m. to a report of a student with a gun.
"The principal told police that a male juvenile student was being verbally disciplined by a teacher when the teacher noticed that the student had his hands in the pocket of his sweatshirt and that he had something in it," Officer Dennis Jensen, a spokesman for the Prince William County Police Department, said in a press release. "When asked what was in his shirt he told the teacher that he had a gun."
Police did not find any guns when the student was searched, and did not find any guns in the classroom.
The teenager was taken to juvenile intake, where a court ordered him to serve 14 days in another county. He has been turned over to that county.