Looking for a chance to get in some humor is a good idea. If it seems forced at all, that would be bad. I know a kid who made Homecoming King. He poked a little fun at himself (not in an essay, but in the activity description), just to let people know he didn’t think it was a really weighty accomplishment. It was an accomplishment, though. He’s a high achiever with decent nerd cred who was also social enough to be elected Homecoming King. Mixing in some humor can really help.