Hayes Middle School near Lomas and Wyoming was evacuated Friday afternoon.
A teacher says a student lit a smoke bomb in a bathroom, setting off the fire alarm and sprinklers.
Students were evacuated while the fire department and police investigated.
“These kids need to learn that this is serious and it costs a lot of money. Every time these trucks come out it’s like $300 the school is charged just for the response and it’s taking these firefighters away from being able to help other people that really need help,” teacher Jonathan Brannon said.
No word on what punishment the child will face.