Child of Earth — David Gerrold

Book one of the Sea of Grass trilogy

Want to visit another world? It might not be as easy as you think.

When Kaer's extended family signs up to emigrate to Linnea, a planet known for horses as large as houses and dangerously mistrustful natives, Kaer is certain the move will bring the divided household closer together. What none of them are prepared for is the grueling emigration training in the Linnean dome, a makeshift environment designed to be like Linnea in every possible way, from the long, brutally harsh winters to the deadly kacks -- wolf-like creatures as tall as men.The training is tough, but Kaer's family is up to the challenge. Soon they begin working like Linneans, thinking like Linneans, even accepting Linnean gods as their own. The family's emigration seems to be just around the corner.

But then, a disaster on Linnea itself changes everything.