I created task cards using some of the key vocabulary words we learned during our book study and numbered the cards 1-21. Over the weekend I pulled out a few sets of the "Let's go fishin" game and numbered each of the fish with a number (hence the 21 question cards.) I broke my students into groups of 4 and had them go "fishing" When they caught a fish they had to answer the numbered task card correctly in order to keep the fish.
While the activity helped reinforce synonyms and antonyms, it was a better lesson in learning how to work together and treat each other fairly. That is a lesson that is well worth the time it took to teach.