The collision happened on Sandy Lane West, all three teenagers have been taken to hospital.
Thames Valley Police is appealing for witnesses following a serious injury crash in Oxford at around 3pm today.
Officers were called to Sandy Lane West, to reports of a collision between a blue BMW 1 series and three teenage children.
One of them has been taken to hospital with fractures to her legs. The other two children have also been taken to hospital but are not believed to be seriously injured.
The driver of the vehicle, a 19-year-old man, has been arrested on suspicion of causing serious injury by dangerous driving.
He remains in custody at this time.
Investigating officer Sergeant Joe Clamp of the Joint Operations Roads Policing Unit, based at Bicester Howes Lane, said: “We are investigating this incident in which three teenage children have been injured.
“One man has been arrested and he remains in custody at this time.
“We are appealing for any members of the public who may have witnessed this collision or may have dash-cam or other footage to please get in touch with us"
You can do so by calling 101 quoting reference 1218 27/01/2021 or you can also report online through our website.