A schoolbus was involved in a collision with two other vehicles along the Padiham bypass.
The incident happened as the bus travelled along the Barrowford Road in Fence close to the junction with Wheatley Lane Road at 4pm.
Police said a Renault Megane and a Vauxhall Zafira were also involved in the collision and needed to be recovered from the scene.
The pupils were unharmed in the crash but the driver of the Zafira had to be taken to hospital for treatment for minor injuries.
A third vehicle was found on the grass verge near the scene when police, paramedics and fire crews arrived.
The road was blocked by the collision but reopened a short time later. Investigations were being carried out into the incident.