How the professor tries and integrates the classroom material to the real world is important. Having to do research on the extra credit molecules every week for my organic chemistry class allows me to realize that these molecules on paper are more than just carbon-carbon bonds. They are what can cause you to have cancer or save you when you are diagnosed with a disease. I find that convincing a student is the first step to teaching a student. When I feel like the instructor values my being there as part of the learning process, then I am more inclined to be motivated to do all the reading etc.
Teachers generally value the student.
But sometimes it seems like the instruction would be exactly the same whether or not I'm there. I leave those classes feeling like it didn't matter if I was there or not. Instructors that require students to write and talk about the material on a regular basis in class motivate me to be prepared because I know that I am going to get a chance to talk, and be heard in the classroom setting. Another way that I'm motivated by instructors is if I feel like they are excited about what they're teaching and can make it exciting for us in the class. I want to close with the idea that I hold to be most true, and that is that there is only so much that an instructor can do in the classroom to motivate students.