Investigators said around 1:40 p.m. the bus driver was making a left from Evans Road on to the Cary Parkkway when he lost control and crossed the median to the other side of the road.
Pictures from Chopper 11 HD showed the bus up an embankment on the road shoulder.
There were approximately 20 children on board at the time. Two were taken to WakeMed Cary to be checked out.
The YMCA says none of the children on the bus was seriously injured.
The bus driver suffered minor cuts.