David,
        Have you thought about having theme dinners or parties?  A Shaker
site in our area has candlelight dinners, using Shaker recipes and then a tour.
I'm sure you could find recipes appropriate to your museum.  One year a museum
in Tarrytown reenacted the events in "The Legend of Sleepy Hollow" with the ball
   in the barn and all (this was for Halloween--of course).  You also could try
a book club, where members read novels that take place during your historical
time period, or by local authors.  Just a few ideas.  You can do so much with
history.  Get some suggestions from your members.  Good Luck.
Ellen Schwartz
[log in to unmask]