The 100 students, all aged 17 or 18, were reportedly refusing to sit down, and continuously playing with their mobile phones.
Asked by the air stewards to take their seats, the students – from the Yeshivah of Flatbush school in Brooklyn, New York – continued regardless.
“The point at which the captain comes on the PA system and says ‘You all need to sit down’ is unusual,” said Brad Hawkins, a spokesman for Southwest Airlines, adding that the cabin crew made “repeated requests” for an unknown number of the students to behave.
“I have no indication that the flight attendants overreacted,” he said.
The flight, from New York to Atlanta on Monday night, was delayed for 45 minutes as the 100 students and their chaperones disembarked.