When must the headlights of a school bus be on?

The correct answer is that the headlights of a school bus must be on at all times when the bus is in motion. This requirement is in place to enhance the visibility of the bus to other drivers and pedestrians, ensuring safety during operation. School buses are often transporting children, and having headlights on serves as a clear signal that the bus is active and should be approached with caution.

While headlights are particularly important at night and during adverse weather conditions, like rain or fog, the law mandates their use at all times in motion to maximize visibility regardless of the time of day or weather status. Additionally, while a bus may need to activate warning signals when stopped at a school, simply having the headlights on while in motion is crucial for ensuring safety throughout the duration of the trip, not just in reaction to specific conditions.