There were only four students on the bus, and all were taken to the hospital for observation.
The accident injured nearly two dozen students.
Missouri education officials say no one was injured when a driver sideswiped a bus carrying six students from a school that serves the severely disabled.
Colorado authorities have charged a school bus driver with drunk driving.
Ten Kansas children and a school bus driver were pulled to safety from a fast-moving creek Thursday after the bus toppled into the water and landed half-submerged on its side.
The incident happened Monday and involved students from Doris Intermediate School.
The Missouri Highway Patrol says two people died when their vehicle hit the back of a school bus about 50 miles east of Kansas City.
Jurors have sided with school bus manufacturers in a 2005 Missouri crash that killed two motorists and critically injured two schoolchildren.
The same type of bullet was also found in February in the hallway of the school in Belleville.
Eleven students from north St. Louis are being treated for minor injuries.