Our preK-4 school has been doing One School One Book for about 10-12 years.  We choose a chapter book, buy it for all the families and ask everyone to read it.  Since many families don't, classroom teachers read some chapters in school.  It is hard to find a book that suits the wide age range from 3 to 9, so I thought of trying One School One Author, and find a chapter book and a picture book by the same author.  Any suggestions?