For thirty-eight years, Dora Kessler had been at the corner of Elm and Fourth every school day from seven-forty to eight-fifteen and again from two-fifty to three-thirty. She had seen the neighborhood change seven times by her count, measuring change by which businesses stayed and which names on the mailboxes changed. She kept this information in her head because it was the kind of information no one else was keeping. The children were the constant, which surprised people when she told them. Not the same children, obviously, but children in aggregate behaved the same way they had in 1986: the ones who ran ahead, the ones who dragged behind, the ones who stopped to show her things they had found on the ground. She made a point of looking at whatever they showed her. A bottle cap. A feather. Once a very small frog that had somehow made it three blocks from the nearest pond. When the city sent her a retirement notice, she showed up anyway. The school principal came out to ask her to stop. She explained that she had a crosswalk and children and a stop sign and she was not sure how the retirement of a person canceled any of those things. The principal went back inside. She stayed until spring, when the city quietly reassigned a replacement without making it an official transfer.