This book was written for kids, probably somewhere between 3rd and 6th grades. It's exactly the kind of book that I would have LOVED as a child. It's about the Thorne Rooms. They are kind of like dollhouses, but they are patterned after real peoples rooms. They are real, I thought that was so cool. This book really brings out your imagination! Ruthie and Jack are on a field trip to the museum when they find a key, little do they know that this key is magical. With this key Ruthie is able to shrink down to 5 inches and go inside the Thorne Rooms. I really enjoyed this book, I know it was written for a younger audience, but Ruthie being able to explore these small rooms really started my imagination going, and of course, my fourth grader LOVED it!!