A framework widely used in the field of industrial-organizational psychology, the Job Characteristics Model (JCM) (Hackman & Oldham, 1976), was applied in the current study to measure the quality of students' service-learning experiences as they relate to student outcomes. It was hypothesized that service-learning projects with higher motivating potential, in terms of characteristics underlying job satisfaction according to the JCM, would lead to greater increases in learner motivation and general self-efficacy. Study participants were 228 students engaged in service-learning courses at five community colleges and one state university in the Northeastern United States. The results showed that changes in students' self-efficacy scores were moderated by the motivating potential of service-learning courses. Furthermore, learner empowerment appeared to be a partial mediator of this relationship. The study provides support for the application of the JCM in designing service-learning experiences to strengthen students' course motivation and self-efficacy.