The concentrated pace of a summer session requires major adjustments. Please have a look at this piece by Anastasia Salter in the ProfHacker blog for the Chronicle of Higher Education. She is is an assistant professor of digital media at the University of Central Florida.
The writer offers practical tips on long-term assignments, remediation, and how to adapt a lecture format to pedagogies better suited to longer classes in a shorter overall time frame. Some mini-mesters, as they are called, have classes that last as long as four hours or more each day. (It's a similar dilemma with evening classes meeting once a week for three hours. And these students have likely worked or taken care of kids all day.)
The weird part is that summer students at community colleges are often very strong academically. As we all know, many young individuals enroll who have been away to selective residential universities and are home for the summer. Consequently, the success rates often go up dramatically with summer classes, even though the pace and intensity (one might say rigor) is greater. If you want to get your numbers up, teach as much summer school as possible. Alert supervisors, however, are aware of the discrepancy in student profiles.
Incidentally, these summer students are usually all too familiar with lecture, perhaps in large auditorium-style classrooms. They may be unaccustomed to speaking up in class, for instance.
The above comparison applies largely to introductory courses in the core curriculum. Those in other fields, especially in workforce training programs, probably don't see much difference between summer students and those who enroll in the fall or spring.