Tunnel in the Sky

Mankind has reached the stars, but not via hyperdrive, or slowboats, or any other non-einsteinian concept. Instead, an accidental discovery has enabled us to warp space directly from the Earth's surface, making that point congruent with one on a world circling another sun. With new frontiers opening every day, students, even at the high school level, are trained in the arts and crafts necessary to survive in a strange environment. The final examination will consist of one week on an unsettled world, alone. ANY planet, ANY climate, ANY terrain. To pass the course, all that is required is that one be alive when gated back to Earth. This is the story of a group of young people taking that exam, but when time is up, there is no recall. They are stranded somewhere, with only the basic survival equipment they brought along. And they must tame a world!