Weltraumkadetten.

This is the seminal novel of a young man's education as a member of the Solar patrol, an elite, paternalistic non-military organization dedicated to preserving human civilization. Space Cadet is a provocative parallel to Heinlein's famous later novel, Starship Troopers (which is about the military) . Only the best and brightest, the strongest and most courageous ever become Space Cadets. At the Space Academy, they train to become part of the elite guard of the solar system. The patrol accepts missions others fear, takes risks no others dare, and upholds the peace of the solar system for the benefit of all. Before Matt Dodson can earn his rightful place in the ranks, his mettle will be tested in the most severe and extraordinary waysways that change him forever, from a midwestern American boy into a man of the Solar Patrol.