Thoughts from a 21st century educator.
This is my BookGUI module, including the most recent updates (which are actually almost a year old). I don't consider it stable for a except for a development environment, but maybe someone can iron out a couple of the kinks I gave up on.
This allows you to edit the structure of a book (AKA the Book module) as well as add/delete pages to the book on the fly, all via an Ajax management page.
It's huge flaw is that it doesn't check for the number of pages that it's going to load. I really need to build some kind of paging system or something similar into this structure. Maybe only load the structure of the book, and none of the content? Content could be loaded on the fly via Ajax...
Anyway, check it out if you like, it's released under the GPL.