Conventional wisdom has long held that students benefit from smaller classes. But that conventional wisdom has primarily been tested in elementary and secondary education -- and some of the research finds that class size is not the key factor for the student experience there.
In higher education, the idea is nonetheless widespread, and colleges boast about their low student-faculty ratios. Rankings tend to favor low student-faculty ratios and U.S. News & World Report explicitly gives points not only for the ratio but also for the percentage of undergraduate courses that have fewer than 20 students in them.
But for a variety of reasons, as outlined in a new research paper, it has been difficult to test the educational merits of small classes in higher education. In an elementary school, a single teacher instructs all students all day long, and school districts generally have standards for class size. Even in high schools, where students move around, teachers tend to have fairly uniform class sizes (by discipline) that go up or down in concert with an entire school. This uniformity makes the K-12 setting easier to study than is a college, where faculty members teach seminars and large classes and many students have a constantly changing mix of the two taught by constantly changing faculty ranks.
But a new study by two economists and released by the Cornell Higher Education Research Institute may have found a way around those methodological challenges -- and the results of the study may raise cautions for those who believe that letting class size or course load grow can be accomplished without an impact on student learning. Given that many colleges have in fact let class size and course load grow during the economic downturn, these findings are timely.
The study was conducted by James Monks and Robert Schmidt of the University of Richmond. They examined 10 years of student evaluations of learning at an unidentified business school where a dean's unusual bargain with faculty members allowed for a study that could better isolate the role of class size and course load in higher education than is usually the case.
The dean gave faculty members the option of "super-sizing" sections so that those teaching three sections could teach two instead. Typically, this meant shifting from three sections of 30 to two of 45. The dean's motive was to decrease reliance on adjuncts without necessarily hiring additional faculty members. The experiment lasted for six years, and many faculty members took advantage of the option. The dean was succeeded by another who, concerned about Business Week rankings that include class size in the formula, wanted to move the sections of 45 back to 30.
Because the university maintained detailed student evaluations of the courses before, during and after the experiment, Monks and Schmidt were able to examine the impact of class size and course load on students -- knowing that professors of roughly the same quality were teaching students of the same quality in sections that covered the exact same course material. In some cases, the choices of the professors also led to an increased number of students taught overall (based on number of sections and sizes), so the researchers were able to study the impact of class size and course load.
The results in analyzing student evaluations showed a clear (negative) impact of increasing class size. "[T]he larger the section size, the lower the self-reported amount learned, the instructor rating, the course rating," the paper by Monks and Schmidt says. The same is true, to a slightly lesser degree, for instructors who teach more students overall (across all of their sections).
Delving further into the evaluations of student experience, the authors find that increasing course size or number of students taught overall "has a negative and statistically significant impact on the amount of critical and analytical thinking required in the course, the clarity of presentations, the effectiveness of teaching methods, the daily preparedness of the instructor for class" and many other factors.
The authors write that the study raises important issues for administrators trying to find ways to improve the student experience. Reducing class size will help, they write. But doing so only by hiring many adjuncts who have to teach so many sections that their overall student load is high may be counterproductive, they warn. Hiring adjuncts or anyone to teach too many sections "ignores the role that total student responsibility plays in how faculty actually teach these courses," the authors write.