Gypsy Rover (You could play the Boiled In Lead version for fun)
Old Time Religion, the original or the many versed parody.
Three Old Ladies Got Locked in a Lavatory.
Barley Mow,
Oh Mary Don't Weep
The best singing I ever had, was when the Smokey City Folk Festival got rained out, and a bunch of us ducked under the bridge in Point Park, and sang "Hard Times Come Again No More". Try that.