A Casino High School student has been hailed a hero after saving a runaway school bus from hitting a busy petrol station.

When the parked bus rolled away without the driver, quick-thinking Year 9 student Izzy Miller took control of the wheel and steered the bus safely away from oncoming traffic, pedestrians, a petrol station, and a Mini Mart.

“I looked over to talk to my friend, turned back over for like two seconds, and the bus started moving,” Izzy told ABC Radio.

“There was no one at the steering wheel. It was heading near the petrol tank and no one was doing anything so I jumped up, got into action and steered it away."

In a twist, Izzy was already due to receive the school’s Black Swan Award for Respect, Inclusion, Safety and Effort, but her heroic efforts made the assembly all the sweeter.