Lulu is a publishing tool for aspiring authors. What I found especially cool about this site is that it has a section for teachers/ students. Here's the dish (directly from their site): "If you're in grades K-8, Aspiring Authors will help you create your very own book. Have your teacher register your class on Lulu and start writing your original story. Each student that completes a book will receive their first printed copy for free."
I will be definitely be looking in to this to use with our fourth graders especially since in Texas 4th grade is tested in writing on the TAKS.