In a few weeks, the back fence by the elementary school with be a place where migrants gather themselves before they leave. The fence is popular because of its temperature and the protection it offers. The sun hits the fence from mid-morning until late afternoon in May, and so many years of sun has turned what must have once been dark wood into a faded gray. But the fence also has a line of horizontal two-by-fours about a third of the way to the top, which seems to be the ideal combination of...