At UGA, we don't have a university requirement in terms of the number of hours of service to be considered service-learning. More important is that the service activities are carefully selected in light of the course learning objectives-- quantity is less the focus than quality of the service activity and its fit with the content. In fact, our research on student outcomes shows that, while there is a small impact from greater number of hours of service, other best practices like the amount and quality of critical reflection are much more impactful on student learning than the time spent.
Likewise, because some service-learning courses engage students with projects or deliverables (such as a website, a community garden, a grant application, or a curriculum) for the community partner, rather than a placement (like one afternoon per week or 15 tutoring sessions per semester), it's not always easy or appropriate to set a number of "hours." However, in the non-traditional format field section in CAPA, faculty members should offer their best estimate of the amount of service-learning incorporated into the course.