I start out by giving the students a graphic organizer with a word and a sentence using the word from the book. The students then look up synonyms for the word, rewrite the book sentence with a "more interesting" synonym, and then write a sentence of their own with a different synonym. Finally we make tombstones for our now dead words and ghosts for our synonyms. All tombstones get at least three ghosts: the "improved" book sentence, their own sentence, and one other synonym that they just think is fun (usually it's the biggest word they can find).
This year we turned out door into our word cemetery, and I've had so many teachers stop by and comment on how much they like it. The sentences aren't exactly perfect, and some of their synonym choices are a bit creative, but they at least understand the basic idea of what a synonym is and it makes a fun display for Halloween.
The templates, graphic organizer, and directions are all available in my teacher shops (just click the link above) and I am giving away 3 copies of it on October 24 (link below). I've also included a pdf download of the vocabulary cards that I made for this book. Happy haunting, everyone!