Christopher Evans 
Dreamtime: Ice Tower [EPUB ebook] 

Rhys Morgan and Jack Dawson are the last two boys on the school bus. It’s the same everyday. But today will be different.Coming down the hill towards Wellthorpe, through a heavy snow laden day, the bus careers out of control and crashes.Into a river and a different world. A world where crows talk. The world of the Icetower and its dark owner. A world where Rhys and Jack must find the strength to be heroes.In Dreamtime, you have to look before you leap. So, do you dare step over the Threshold?