A school bus and a light truck have collided in Sydney, prompting the assessment of eight children for minor injuries.

The two vehicles collided about 2.25pm (AEST) on Friday on Windsor Rd, at Kellyville, in the city's northwest, police say.

A total of 28 people were travelling in the bus at the time of the incident.

Paramedics at the scene continue to assess the children but no one has been transported to hospital, a NSW Ambulance spokeswoman said.