What must a slow-moving school bus do when it has five or more vehicles following it on a two-lane highway?

When a slow-moving school bus has five or more vehicles following it on a two-lane highway, it is required to use a turnout. This action helps to alleviate congestion and improve traffic flow.

Using a turnout allows the bus to safely pull over to the side of the road, which permits the following vehicles to pass. This is critical in preventing frustration among other drivers and maintaining safety on the highway. In many regions, this practice is part of defensive driving techniques encouraged for school bus drivers. It emphasizes the responsibility of the bus driver not only for their passengers but also for the overall traffic situation.

In contrast, speeding up to match traffic may not be advisable or safe for a school bus, which is usually required to maintain a slower speed for the safety of the children on board. Turning on hazard lights is an important safety practice, but it does not resolve the need to allow other vehicles to pass when there is a line of traffic behind. Pulling over to the side may be unclear without specifying to use a turnout, and could be less effective than a planned turnout point.