This study compared workloads of undergraduate courses taught in 16-week and 8-week sessions. A statistically significant difference in workload was found between the two. Based on survey data from approximately 29,000 students, on average students spent about 17 minutes more per credit per week on 16-week courses than on similar 8-week courses. For selected general education courses taught in both formats, a similar result was obtained. When disaggregating results by subject and instructor, we found that the subject and the instructor of the course are more likely to be the cause of any significant difference in rigor based on workload.