Maybe that’s true in your state, but not here in WA. If there is a “When children are present” sign only, it means when there are children using the crosswalks or shoulders along the roadway within the posted school zone.
Theres an unwritten rule…if you are a commercial driver, there is always a kid in the school zone.
It’s actually not the school zones that annoy me, it’s the drivers who don’t think the law applies to them. Even if there are no children, but there is a sign that says school zone 20mph (when light is flashing) and the light is flashing, someone is usually trying to push me down the road because I’ll actually do 20mph from sign to sign while the person behind me comes unglued.