Symbolically Challenged

I'm four chapters behind in my symbolic logic class. I've been struggling to get caught up the last two weeks, but the harder I try to get ahead the more I feel stuck. I'm spinning my wheels, running in place and I can't get passed chapter four!

I get the rules. I see them, and while they don't make a whole lot of sense, I do understand them enough to apply them - at least I think I do. It's just when I get to the derivations of disjunction elimination I get a 'deer caught in the headlights,' glazed over look of confusion.

The first part I can do, no problem. After that, though, I'm completely lost. Looks like I'll be spending my Saturday in the lab working on symbolic logic and getting help from the class assistants.