Seven-Day Magic, Paperback

All books are magic, but some are more magical than others.
When Susan opens a strange library book, she discovers it is about her and her friends, leading up to the moment when she opened the book. Beyond that, the pages are blank . . . waiting for the children to wish the book full of adventures.
Fredericka asks for wizards and beasties, and a dragon carries her off. Susan journeys to the world of Half Magic, and finds that mixing magic creates trouble--far too much to deal with before the book is due back at the library.
Wishing, it seems, is a tricky business. And if the children make the wrong wish, their adventure won't end, as all stories must, happily ever after.