I put a goodie underneath one of those little plastic bathroom cups and have them hunt for it.
At first even though they watched me they didn't really catch on to the whole thing but now one of them will immediately start pushing the cups to reveal the goodie. Makes great video clip opportunties.
I've found them to be quite playfull. We have three cats. An all black male, a calicote female and the B&W female in the picture. I get a kick out of them while they are running around hiding from each other then wrestling. Have fun and Thank You.