Originally Posted by
Mitch's mom
You may end up dealing with her for this class. In the future you could possibly put on the bottom of your class hand outs and sign up sheet: Due to limited class size and the nature of the instruction no Guests are permitted in the class room.
Along with PatriceJ comment, this may also be the best way to do it. I never had this problem before and when I have taken a few classes, usually I didn't know anybody in the class either.