Unfortunately, I do not have a study unit already written for this wonderful book. However, I recommend using the eNotes resources at the link given below. The links to the right of the page will help you address various aspects of the book. Good luck!
Edhelper has a study unit including vocabulary. I am also going to have my class read this book in the fall. I have found the Edhelper units to be educational, but they tend to use surface knowledge only.