How about numismatic learning in the form of quizzes?...you get CC$ for correct answers and can cash in points down the road for prizes

correct answers equal 5 points 10 points and 20 points
accumulate 75 points and get modern MS penny...150 points,etc.
end of year highest point total gets big prize!
Members submitting quiz questions and/or prizes get points..
set up beginners and advanced level Q&A
after writing all this it sounds like too much work

Atlashealth