Perhaps one way to do this is to help them to succeed in class each day, and therefore improving their competence and self-worth. As we saw in class today, a little competition can go a long way, especially when food is involved. I've always been a fan of in-class trivia games; it fuels my competitive side and allows me to work better with my peers as a team. Participating in these kind of games allows each student to trust their peers a little more. I am also an advocate of extrinsic motivators like candy/cookies/ice cream. While I believe that intrinsic motivation is more important, it is also okay to be extrinsically motivated. Take Ed Psych for example: I enjoy this class on many levels. I feel that I'm learning a lot already, and I am genuinely interested in each topic (so far). However, I also understand that this is a required class for my degree and that I must succeed in it to gain the ultimate prize: a job.
So we, as teachers, need to be careful about the tasks we assign. "Busy-work" is one of the biggest ways to make me feel as if I'm not being challenged, and if I'm not being challenged, what's the point of paying attention in class? If a student believes that a task is too hard, then they will not push themselves to complete it; I know because I've done this many times. On the other hand, if the task is too easy, a student might believe that they are better than the work I have assigned and may choose not to complete it. We need to find a good balance between fun activities and educational ones.