The gunman was wounded and subsequently took his own life, authorities said.
The suspect, identified as Clay Duke, 56, of Bay County, Florida, spray-painted a wall and then opened fire on the superintendent and school board members during the meeting, authorities said.
The gunman apparently missed each person he fired on, even though he was at close range, said Lee Stafford, director of student services of Bay District Schools.
The chief of security for the school board shot and wounded the man, who then fatally shot himself, said Ruth Corley, a spokeswoman for the Bay County Sheriff’s Office.
The harrowing incident was captured by a live internal feed of the afternoon school board meeting.
CNN affiliate WMBB showed some of the confrontation, during which the gunman and a school leader discussed sales taxes and other issues after the gunman ordered other people out of the room.
At one point, the official said, “I don’t want anybody to get hurt. I’ve got a feeling that what you want, is you want the cops to come in and kill you because you are mad. Because you said you are going to die.”
“This isn’t worth it,” the official says. “This is a problem.”
The gunman then points the pistol at the official.
“Please don’t. Please don’t,” the official says.
At that point, the gunman opens fire on the official and school board members until he is brought down by a gunshot. He says, “I’m going to kill [unintelligible],” while he fired.
Investigators scrambled to understand what happened.
“We do know who he is, but cannot speak to any possible motive,” Corley said. “The detectives are still conducting interviews with witnesses.”
The man, who had a handgun, ordered people out of the room before confronting the board members who remained, Stafford told CNN.