Fablehaven by Brandon Mull
Kendra and Seth are forced into a vacation with grandparents they have hardly ever seen. Grandpa Sorenson, persuaded by their parents, is reluctant at best to have children stay at Fablehaven.
Unknown to the family, Fablehaven, has been a sanctuary for mystical creatures for centuries, a stronghold of true magic in a changing world. Grandpa and Grandma Sorenson, caretakers for the refuge, never had anyone come to stay.
Kendra and Seth are not sure about what they are about to encounter. It appears that they are going to stay in the attic playroom. Expecting it to be full of dust and cobwebs, they find they will be sharing the space with a chicken!
Grandpa Sorenson, has a long list of rules about what they can't do and while Kendra is prone to follow them, Seth is just as determined to break them. Day 1 he sets off for the woods where Grandpa Sorenson told them never to go.
Before the week is out, strange things begin to happen, and as Grandpa Sorenson learns to trust them, they begin to learn about the unusual creatures who live at Fablehaven...
(rated Young Adult grades 5 and up)