To play, first write all the terms on the board. Then have students line up in two lines. The first students in line listen as you read the definition then have to be the first to "splat" the word with the fly swatter and call out the correct word. We didn't keep points, just kept it moving fast to help students grow in their familiarity with the terms.
I forgot to take a picture of our class, but here is a pic from another blog (2nd Grade Pad) with a math fact review game so you can get the gist. You could totally use the desk tops with cards just as easily as writing the terms on the board.