Dear Answer Man: I live near two school zones with speed restrictions "When children are present." "The establishment of a school speed limit on any trunk highway shall be with the consent of the commissioner of transportation." Basically, if kids are outside and they are in a school zone, the school zone speed limit is in effect. Chances are the speed limit there is already down to 25 mph, so those drivers should already be taking it easy. So, if a school is located on a state highway, for example, with a usual speed limit of 60 mph, the school zone speed limit can drop traffic down to 30 mph.