The Haunted Hotel

I liked this book when I was in elementary school. It's great for kids who like spooky mysteries. Laura and Bill are visiting their uncle, who is the caretaker of a large hotel in New Hampshire. The hotel is closed for the winter because it is too old and poorly-insulated to heat. The children think that the big, old hotel is fascinating, especially when they begin hearing stories about the ghost of a princess who is said to haunt the hotel and put people under her spell to do her bidding. When the children begin noticing that their uncle is behaving strangely, they start to wonder if he is under the princess's spell. Even though their parents have forbidden them to go inside the old hotel, Laura is determined to investigate the mystery, just like the main character in her favorite series of books.