Trucker's hitch? Figure eight? Bowline? Square?
You can all blame KD for roping me into this. (ouch) I'll bring some rope and we talk about some knots. More than likely I'll start philosophizing half way through them about the essence of being a knot. But should be fun anyway.
This is not really a full-hour workshop. It could easily a half hour to practice a couple of knots, but learn as many or as few as you want. Come in beginning, middle, whatever.