One appliance and crew from Beaconsfield, one from Langley and one from Amersham attended, along with one officer.
One car was on its side in lane 3 of the motorway when they arrived.
The firefighters righted the car.
One boy and one girl were treated for minor injuries by South Central Ambulance Service.
Thames Valley Police also attended.
The motorway was closed while the emergency services were on the scene.