What is it? The amount of work it takes to do well in a course? The amount of time it takes to complete the work assigned in a course? The amount of time students actually spend studying and completing assignments? It's a term that's often used generically without a sense of its precise meaning.
Moreover, course workload is used in discussions much more frequently by academics than by students. Students talk about whether it's a hard course and their use of that descriptor is equally generic. Is it hard because the course contains lots and lots of content? Is it hard because the content itself is new and difficult to understand? Is the course hard because there's lots of time consuming assignments? Or, is it hard because the teacher makes it so by being disorganized, unable to offer clear explanations and unwilling to work with students? Students also apply the “hard” descriptor to faculty, generally meaning they're tough graders. It isn't easy to earn an A. Students must follow instructions and pay attention to details in addition to having first-rate content.
If it's a “hard” course one would expect that students would devote more time to the course. That's one of the reasons faculty aspire to teach courses that “challenge” students, courses with “academic rigor”. Most faculty don't aspire to teach “hard” courses, meaning courses design so that they prevent learning or make it more difficult than is necessary.
The research on course workload and on hard courses doesn't resolve the definitional differences but it does offer some interesting insights. David Kember's work is classic. He starts by identifying a key distinction. Course workload can be defined as the number of hours worked on the course, but his research documents that “perceptions of workload are not synonymous with time spent studying, but can be weakly influenced by them.” (p. 165) Rather, students respond to courses based on their perceptions of workload (as opposed to some objective measure of it) and those perceptions are influenced by a range of variables including course content, difficulty, type of assessment, teacher-student relationships and student-student relationships. This means that a student may be devoting a modest amount of time to a course and still reporting that the workload is heavy.
Kember's work along with that of other researchers does consistently report that when student perceptions of the course workload are heavy, they tend to avoid deep learning approaches. Kember writes about this body of research, “from these studies it would be reasonable to conclude that excessive perceived workloads can have a negative influence upon student learning through being associated with a tendency to encourage surface approaches to learning.” (p. 168)
Other work on course workload (Martin, et. al) offers evidence that contradicts belief that students always prefer easy classes. The engineering student cohort studied by Martin and colleagues expressed preferences for courses that were challenging, but challenging up to a point. Substantiated in this work and that done by others, student attitudes change if the workload is heavy and the task so difficult that it appears impossible even with great effort. “Once the course was perceived as being too difficult, the students developed a mild to severe dislike for the course and typically for the instructor as well.” (Martin, et. al, p. 109) Kember offers a similar conclusion. “Piling the work on will eventually become counter-productive as students resort to short cuts and undesirable study approaches to cope with the excessive demands.” (p. 182)
A more recent exploration in these areas looked at the nature of academic rigor (Draeger et al. 2015) from faculty and student perspectives, and found significantly different understandings of the concept. Faculty cared about higher order thinking skills. They assumed that learning took time and hard work, but that effort was what was needed to master the material and acquire the skills of the course. Students, on the other hand were not interested in higher order thinking skills. They talked about the difficulty of course, the workload and their grades. They were more focused on meeting faculty expectations than on mastering the learning outcomes of the course. Bottom line: the students didn't care about the academic rigor of the course. They were interested in whether or not it was a hard course.
The research and these widely varied understandings of course workload leave the set of opening questions pretty much unanswered. Perhaps a better place to start is with a more personal question set. Do students think your courses are hard? What would they say about the workload? How accurate are your estimates of the workload? What do students consider hard/easy about your courses? The answers are important because as Kember points out, “teachers and course designers are very important elements in influencing the way students approach learning tasks.” (p. 182) Students have been known to work long and hard in courses. They do so because they are motivated, the task is intriguing, the teacher is there with support and they've been persuaded that their hard work with pay off with grades and learning.
References: Kember, D. (2004). Interpreting student workload and the factors that shape students' perceptions of their workload. Studies in Higher Education, 29 (2), 165-184.
Martin, J., Hands, K., Lancaster, S., Trytten, D., and Murphy, T. (2008). Hard but not too hard: Challenging courses and engineering students. College Teaching, 56 (2), 107-113.
Draeger, J., del Prado Hill, P., Mahler, R. (2015). Developing a student conception of academic rigor. Innovative Higher Education, 40, 215-228.