What condition must be met for a school bus to legally load or unload children?

The requirement for a school bus to legally load or unload children is that it must display its flashing red lights. This is crucial for ensuring the safety of children entering or exiting the bus. The flashing red lights serve as a signal to other drivers that they must stop their vehicles and not proceed past the bus until the lights are turned off. This precaution helps protect children who may be crossing the street or standing near the bus while waiting to board or after getting off.

Having the bus in a designated bus stop area is important for organization but does not serve as the primary safety measure for loading and unloading children. Maintaining speed is not applicable since the bus needs to be stopped and stationary when children are boarding and alighting. Also, while it is essential for students to be seated before the bus resumes moving, this requirement comes after the initial safety measure of activating the flashing lights. Thus, the activation of the flashing red lights is a critical part of the process that prioritizes children's safety when they are near the bus.