We could add a section that it says wizard or witch of the day and that his or her avatar appears. It would be the one who has had more mentions at the day. Hope you like it!
That way it will become a competition if someone's being mentioned and people might abuse this function in chat.
What Thomas said. Maybe it can be something like, graded most homeworks, posted most topic replies :)
This can make other users feel upset if they never get featured, and if it goes by stats, people who have been on the site longer will have an easy time staying on the top while new users would struggle to catch up.
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