What action is not advisable while driving a school bus?

Fueling with riders on board is not advisable while driving a school bus due to safety concerns. When a bus is in motion or occupied by passengers, especially children, there is an increased risk of accidents or emergencies. Fueling requires attention to the process, and the presence of riders can create distractions or complicate the procedure. Moreover, it poses a potential hazard in the event of spills or accidents involving flammable materials.

In contrast, conducting a route briefing is necessary for ensuring that everyone on the bus understands the expectations and procedures, which helps maintain safety and order. Making quick stops for students where necessary follows established protocols to ensure that students can board or disembark safely, and looking in mirrors regularly is crucial for maintaining awareness of surrounding traffic and ensuring the safety of all passengers while driving.