We've been wanting to do coffee classes in our shop on Saturday afternoons.  Either cheap or free.  Depends on what it actually costs us.  These classes would be aimed at our customers and would be rather basic.  Things like coffee vocabulary, Brewing methods, cupping, roasting classes (home roasting), history, etc.  Anyone out there ever done things like this?  Any hints on how to make it work better?  Anything you wish your customers knew?