Ideas for my facebook group?

So basically, ive started this group on facebook that was like, "we should all be good people from now on, yay". obviously, it's done me a lot of good. i have a whole bunch of people, but it hasn't really done anything i'd wanted it to.... like make SOME sort of difference. do any of you hav an idea as to what i could do to haave these people do something??? like an incentive or something??? i was thinking of doing something like have everyone document ONE goo dthing they had done in the past like day or week or something like that... idk,... got anything for me??