«Beyond the Cherry Tree» by Joe O'Brien

Josh Bloom is on a field trip with his class to Cherry Tree Manor; while the house and gardens are beautiful, what really interests the class is the fact that Manor's owner, General Edgar Pennington, disappeared mysteriously exactly twelve years to the day before their visit to the Manor …
To Josh, it seems like there's something spooky about the manor. None of the other kids feel it, but Josh seems more attuned to the house, which leads him to discover something in the General's library that sends him on an adventure of a lifetime.
Josh thinks he is on a journey to find the missing General, but soon discovers that it's his own destiny that he is really searching for … there are links between him and the missing General that he never could have guessed … Josh quest takes him to the enchanting land of Habilon, full of danger, excitement and magic.
Will he ever return from the land beyond the Cherry Tree?