Mining the Genre Asteroid: Rite of Passage by Alexei Panshin
A century and a half after Earth has been wrecked, humanity exists in two spheres. There are the hardscrabble colonies, where survival is the watchword, as man tries to live on alien, often unfriendly environments. The people are often poor, desperate and technologically backward. And then there are the Ships that travel the spaceways. Technologically advanced and relatively rich, the Ships have a strict regime for keeping themselves from being overpopulated. Every person who reaches their fourteenth birthday must train for an ordeal called the Trial.
