We’ve all driven past them dozens, perhaps hundreds, of times but signs reading “Slow: Children at Play” probably aren’t slowing us down, according to a story on Slate.com. The reasons are simple: they are either redundant (because drivers are more likely to see actual children at play rather than a sign telling them about the children) or drivers ignore them completely (because they never see any children at play on the street). What matters, studies show, is traffic speed, not signs. Children are safer on streets with a lower speed limit. As the speed limit increases so does the danger for children. But traffic engineers face a difficult task convincing parents that their children are no safer with the signs than without. Parents, understandably, will take whatever steps they can to keep their children safe. But Slate suggests that the problem is systemic. Our streets are designed for traffic, not for people or neighborhoods or children at play. “It’s roads, not signs, that tell people how to drive,” according to the story.