Princess Galloway's days as a D.C. gang member began innocently enough: She and her childhood friends had birthday parties, talked about clothes and held sleepovers at one another's houses. "It was, like, a normal thing females do," says Princess, 16. As the girls grew older, the parties became nighttime outings to go-go clubs. Belts and bags were replaced by blades and bats as accessories. A girl gang was born. "We started fighting when a different female gang from uptown jumped one of our friends," says Princess, an honor roll student at Spingarn High School in Northeast who quit her gang...