One spring morning this year, Darlene Lomax was driving to her father’s house in northwest Philadelphia. She took a right onto Germantown Avenue, one of the city’s oldest streets, and pulled up to Germantown High School, a stately brick-and-stone building. Empty whiskey bottles and candy cartons were piled around the benches in the school’s front yard. Posters of the mascot, a green and white bear, had browned and curled. In what was once the teachers’ parking lot, spindly weeds shot up through the concrete. Across the street, above the front door of the also-shuttered Robert Fulton Elementary School, a banner read, “Welcome, President Barack Obama, October 10, 2010.”