I will grant you that my opinion (indicated as such in the first post) is just that, opinion. I'll take a look around for studies to support my claim. The main idea that, as the student, I am going to pick up on your attitude or mood and am likely to adopt it. Sure, if you're teaching a higher level course or grad courses the people there are already interested in what you have to say, you're walking into a receptive audience. What I was considering (and should have made clear) was 100 level courses where you have students who, for the most part, don't care walking in. If you can get them to change their mood, it is my opinion that only then can you make them receptive to learning. And I certainly don't mean higher grades (although those would probably follow), I'm talking about understanding concepts. Because, lets face it, if I'm not interested in or excited to learn about something I'm probably not going to retain it beyond what I need to know for the test (after which its going out the window). If you can change my mood/attitude you may be able to get me to be open to learning. Of course I need to be engaged, you getting pumped up about it isn't going to make me learn, but it may make a hostile audience more open to becoming engaged.