My all time favorite chapter book to teach with is "Charlie and the Chocolate Factory". Historically I have saved this chapter book for the last month of school. It is so captivating that it keeps the student's engagement up. At the conclusion of the book, we always have a candy day. We compare the book to the movie and taste test some candy. It's nice to give out candy as it appears in the movie. The kids get a kick out of tasting the gobstopper when it's introduced in the movie.
Wonka makes a nice selection of candy. The 12 ounce bags are the best price per ounce.
If you need a companion to use with the book, check out the unit "Wonka For Candy"!