Many college students in the United States take longer than four years to complete their bachelor’s degrees. Long time-to-degree can increase higher education costs by billions. Time-to-degree can be reduced if students take more credits each term. While academic momentum theory suggests that additional credits may also improve student performance, and there is a strong positive correlation between course load and student performance, high course load may reduce time investment in each course, giving high course load a negative causal effect on performance. Concern about the negative impact of course load on performance, especially for struggling students, may lead to pushback against policies to reduce time-to-degree by increasing course load. Using longitudinal data from a regional four-year university with a high average time-to-degree, we find no evidence that high course loads have a negative impact on student grades, even for students at the low end of the performance distribution. This result is consistent with a model where students substitute time away from non-education activities when their course loads increase.

美国的许多大学生需要四年以上才能完成学士学位。获得学位的时间长会使高等教育成本增加数十亿美元。如果学生每学期获得更多学分，则可以缩短获得学位的时间。虽然学术动量理论表明，额外的学分也可以提高学生的表现，并且课程负荷与学生表现之间存在很强的正相关关系，但高课程负荷可能会减少每门课程的时间投入，从而使高课程负荷对成绩产生负面的因果影响。担心课程负担对表现的负面影响，尤其是对于学习困难的学生，可能会导致反对通过增加课程负担来缩短获得学位时间的政策。使用来自具有较高平均获得学位时间的地区四年制大学的纵向数据，我们没有发现任何证据表明高课程负荷对学生成绩有负面影响，即使对于成绩分布低端的学生也是如此。这一结果与当课程负荷增加时学生将时间从非教育活动中替代的模型一致。