On my youngest daughter's board (high school), we have a different game weekly. Everyone knows the new game goes up on Monday at 4:30 pm and comes down on Saturday at midnight. Her users have a lot of fun with it. Nobody takes it serious as it is not a gaming site. We post things like "most interesting score", "slowest game on record", "best misuse of time", "David played for 2 minutes and Died, but it was an honorable death ... and so on. Most of the game data we exaggerate in some way just to have some fun with the users.
She now has a team that finds the new games and assists her in implementing them on Sunday. (Less of Dad's time. finally.

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In our experience the users have more fun with it when it is just a quirky thing to do. Anyway, just some input. I hope it helps.