Go to a community college or college near you and ask the Chemistry class if they can do some fun experiments in front of an audience.
OUrs just did a "Science Day" for the moms and dads, it was parent weekend and they burned salts, made "gold" out of pennies, put balloons in dry ice. It took about an hour.
It was very entertaining.
Or ask their orchestra to come and play.
Do they have a theater dept?
College kids need audiences and elementary schools are good candidates.