Robert A Heinlein

"The final exam for Dr. Matson's Advanced Survival class was meant to be just that--only a test. But something has gone terribly wrong, and now Rod Walker and his fellow students are stranded somewhere unknown in the universe, beyond contact with Earth, at the other end of a tunnel in the sky. Stripped of all comforts, hoping for a passage home that may never appear, the castaways must band together or perish. For Rod and his fellow survivors, this...