The injured were 43 children and the bus driver, as well as other adults who were aboard the bus, said Mannheim police spokesman Christoph Kunkel.
Three helicopters and 10 ambulances rushed to the scene in the town of Eberbach, about 50 kms east of Mannheim, to bring the injured to area hospitals for treatment.
The bus crashed just after 7 am as it was driving around a left-hand bend in the road in Eberbach.
A wide area around the accident scene was shut down to traffic as the incident is investigated.