Puzzles usually engage students and give them an opportunity to review vocabulary. Here are a few resources to help you create puzzles for your students:

Eclipse Crossword Creator is free software that you can download from home (it is currently blocked on the SCUSD network since it is a game)

Lantern Fish/ Boggle's World has a crossword page that has ready to use crosswords

Discovery Education has an online puzzlemaker that makes several types of puzzles. You can also buy a  CD version.