A VERY good article covering children's literature and writing:
http://www.msnbc.msn.com/id/8917828/site/newsweek/
http://www.msnbc.msn.com/id/8917828/site/newsweek/
Children may be a great audience, but if they really want your attention, they'll tell you what you want to hear. Besides saying "Yuck" and "I didn't like it" or "I loved it," their critical vocabulary is not up to what I need for rewriting a book.