in a school zone, when must a driver stop?

A driver must stop in a school zone when directed by a signal or crossing guard. This is to ensure the safety of students who are crossing or about to cross the street. Additionally, drivers must stop for school buses when the bus has its stop sign extended and red lights flashing. Drivers should also be cautious and drive slowly in school zones, adhering to posted speed limits and stopping for pedestrians in crosswalks.