while I'm driving near schools I often notice street signs that say something like, "speed limit 15 mph while children are present". I am curious what this means specifically. Does it still count if any child is in school? What if they're outside, but in a fenced area? Is there some specific distance from the road that drivers need to be aware of?
What is the specific meaning of these types of signs?
Legally speaking, it's hard to say, because it depends on the laws in the particular jurisdiction. There is a wide variation in how these warnings are phrased, and how they relate to local law, for example it may be limited to "when flashing" (which seems to be the pattern in Washington, but that's more a matter of practice than state requirement). Federal Way WA can indicate school speed limits "when flashing" or "when children present", in case
1.) School Children are occupying or walking within the marked crosswalk.
2.) School children are waiting at the curb or on the shoulder of the roadway and are about to cross the roadway by way of the marked crosswalk.
3.) School children are present or walking along the roadway, either on the adjacent sidewalk or, in the absence of sidewalks, on the shoulder within the posted school speed limit zone.
It appears that "when present" is a theoretical option in that town, and instead they rely on flashing lights and photo-enforcement. This definition follows from a state administrative rule 468-95-335 that defines "when children present" this way, and the state no longer uses the "children present" standard. In another state / town, the law could be different.
It means: If you spot a child you immediately reduce the speed to 15mph. If there is a child that you don’t spot you also reduce the speed to 15mph immediately - so you better watch out for children. If you are absolutely sure there are no children you realise that the sign is there for a reason, so if you decide to go over 15mph you go very carefully.
