The bus had been bringing the pupils back from an excursion to the well-known archaeological site of Karatepe outside the city of Osmaniye yesterday when it flipped over into the canal, the Dogan news agency reported.
It said that the driver had lost control of the vehicle and an investigation was underway.
Twenty four people were being treated for injuries in hospital. Of those killed, three were female pupils, three were boys and eight were adults, it said.