Police say 68-year-old William McCartney, of Harmony Township, was upset that the boy wouldn't remain seated on Nov. 18. About two dozen students also flew into seats in front of them or onto the floor. None had to be treated, but some had brush burns.
McCartney was charged Monday with reckless endangerment, disorderly conduct and reckless driving. He didn't return a phone message.
The boy's mother says her son and the driver have had run-ins before and her son was being singled out.
McCartney has been taken off the route. Ambridge Area School District officials are also investigating.