I was looking at your article regarding thread tags and I do not have the 'Classes' category I can mouse over. How do I create that category? Sorry if it is obvious and I could not find any threads on the support page that talked about this if there was one made already.

It actually is created when you create the tag.
Admin > General Settings > Thread Tags

So all you need to do is create a Tag for each class and make sure that in the Thread Tag Category field you give them all the same name.

Thank you so much!!