Peter Felten and Patti H. Clayton's chapter "Service-Learning," in the Winter 2011 issue of New Directions for Teaching & Learning, provides an excellent introduction to service learning. They cite two definitions of service learning:
"Service-learning is the various pedagogies that link community service and academic study so that each strengthens the other. The basic theory of service-learning is Dewey’s: the interaction of knowledge and skills with experience is key to learning." (Ehrlich, p. xi)
"Service-learning is a course-based, credit-bearing educational experience in which students (a) participate in an organized service activity that meets identified community needs and (b) reflect on the service activity in such a way as to gain further understanding of course content, a broader appreciation of the discipline, and an enhanced sense of personal values and civic responsibility." (Bringle, Hatcher, and McIntosh, p.12)