I have found this book to be fairly helpful. Their are many different kinds of exercises and the book is easy to figure out so it's simple to flip through and pick and choose rather than having to read the whole book cover to cover. The only thing that is a little unfortunate is that their are activities for those who suffer from overeating as well as anorexia and/or bulimia. While I understand why they're all put together in one book, I personally can not relate to the activities which do not apply to my disorder and I just wish that it had been separated into two different books.
While I purchased this book because I have been diagnosed with an eating disorder, I can also see how it would almost be even more helpful for someone who hasn't been diagnosed because it helps to advise teens as to what kind of behavior is normal and can make someone aware of behavior which may be leading them towards a more serious problem.
Overall,I would say this is a worthwhile purchase.