If service-learning will be mandatory, you should make this clear from the first day of class. Schwartz considers service-learning essential to his course and, therefore, makes it mandatory for all students. This may not always be practical, especially in large enrollment courses. It will take a great deal of time and effort to find and set up placements for 100 students as opposed to 20 or 30. More importantly, service-learning enables instructors to create courses that take into account a variety of learning styles.
Some students learn well by reading, taking part in class discussions and writing papers and exams.
Others are more successful when they gain hands-on experience that enables them to put abstract ideas into context. Students in the former category might not be comfortable in a work environment until they are confident they have mastered the course material. If you decide to accept a fixed number of students to participate in community service, you need to work out some type of selection process. There are a lot of people with great G.P.A.'s that are going to have a hard time on the job market because they don't have skills like cooperation and commitment. I also wanted people who had a real desire to give to the community, and sometimes they are academically weaker students.