Kingdom Under Stone (The Forgotten World of Rone)

Five high school students; Hex, Grant, Tia, Emmy and Oscar take on an ambitious project for a class assignment. Their plan; to explore the caverns of the native Atlan tribe. They, however, find more than they bargained for when they are transported to the land of Rone, a place where myth and legend are reality. Now they must learn to trust their new friends, each other, and themselves if they are ever to escape and make it back home alive. But before they do that, they must survive the horrors that lurk in the abandoned home of the dwarves deep inside the mountain. Will their new friends and allies be enough to survive or will they end up joining the fallen? This is the first book in The Forgotten World of Rone series.