In the seventies and early eighties, the New York street photographer spent his summers on the road taking pictures of young Americans at leisure. His black-and-white pictures tend to sneak upon teen-agers who seem suspended between boredom and excitement: making out, hanging out, anticipating their next diversion. McDonough’s group portraits-particularly one of a randy foursome gathered by a parked car in Florida-are terrific, at once spontaneous and composed. But one of the show’s best pictures catches a girl by herself, taking in the sun at the curb of a shopping center near a bunch of empty shopping carts. Through May 5.