Parents waited in line for 96 hours to register their children for the Penn Alexander School. It was proof of the growing commitment of middle- and upper-middle-class parents to public education. “Gentrifiers often feel like they’re making the city and schools better. There’s a very strong sense that they’re part of the solution, and there’s a certain frustration with being criticized,” said Maia Cucchiara, a Temple professor and author of the forthcoming Marketing Schools, Marketing Cities: Who Wins and Who Loses When Schools Become Urban Amenities.