Class Size and Student-to-Faculty Ratios: What the Statistics Don’t Tell You

When a client asked me the other day about the importance of student-to-faculty ratios, I got to thinking about other supposed indicators of educational quality.

The other oft-cited statistic when visiting an admissions office is “average class size.” As with student-to-faculty ratios, the size of the classes at a college is assumed to reflect the quality and the intimacy of the educational experience. Small classes–so the assumption goes–are interactive and provide ample opportunity for interaction between students and faculty. The pedagogy of these classes is more a facilitated discussion than a lecture.

This assumption is generally true: small classes are more interactive. Yet I could cite numerous examples of professors I have known who stand and deliver lectures from prepared notes to a class of seven students. Just because a class is small doesn’t mean it’s any good.

The use of the “average class size” can be very misleading, however, and masks some more important facts about the quality of education delivered by a college or university.

Consider how the following scenarios have an impact on how “average class size” is calculated.

• Some of the smallest classes are taught by the least effective, least popular professors. In a world of university tenure, bad professors cannot be chased out. So they end up teaching ever smaller numbers of students, while the more effective, popular instructors see their class sizes swell.

• Some of the smallest classes are in obscure subjects. Some of these are new courses professors are trying out for the first time. They can be experimental. And few students are willing to take risks of this sort (credits are too expensive, too dear to take such risks).

• Class sizes in some departments are much smaller than in other departments. Courses for popular majors such as history, economics, and biology may be large, while equally good courses in anthropology and art history may be tiny. Here quality of the individual course is not the issue–it’s the popularity of the major that may affect class size.

• Professors generally do not like teaching huge courses–not because they hate lecturing–but because they hate grading so many tests and term papers. So they ask administrators to cap enrollments, insisting that “small classes are better” (when, in fact, they are simply concerned about their own work load).

• Professors and administrators cap enrollments in popular courses in order to keep the average class size small. Even the most popular courses at small, liberal arts colleges are not allowed to grow large–because those colleges are protecting the ratio. In a competitive environment that values small class sizes over large ones, institutions of higher education are loath to allow classes to grow too large. So from an administrator’s point of view, the question is not so much access to great courses or the quality of the individual course (some large lecture classes in the hands of an outstanding professor can be awesome). An administrator’s job is to keep “average class size” as low as possible.

This final point leads to some very troublesome effects on college campuses. An article in the March/April issue of alumni magazine of my alma mater, Dartmouth College, points out that the real, untold story is how the mania to protect the “average class size” statistic is shutting students out of popular courses. The article makes the point this way:

In [the department of] economics, with 453 students registered as majors, minors, or modified majors, students get closed out of as many of 20 percent of their course choices, a rate that far exceeds the rate of closeouts campus wide, as estimated by [Dean of the Faculty Carol] Holt.

To further elaborate the point, a “small class” in the economics department at Dartmouth is 30 students: the department would likely cancel a class with such “low” enrollment. While in the department of anthropology, a “small” class might be 5 or 6 (in my department at the University of Denver, a course with fewer than 7 students was considered “uneconomic” and therefore cancelled).275px-dartmouth_college_baker_building.jpg

(Note to future economics majors: if you really want to small classes, go to a college where economics is NOT a popular major.)

Believe me, this is not the sort of information you will hear from an admissions counselor. They will sing out their statistics on student-to-faculty ratios (8-to-1 at Dartmouth) and “average class size” is probably around 15 or so.

But the statistics, beautiful though they are, do not tell you the whole story. In fact, they can be grossly misleading. And they do not necessarily bear any relationship to the quality of the education being delivered.

As an alumnus, of course, I would tell you that the quality of the education at Dartmouth is more a function of the quality of the faculty and the quality of the student body. Dartmouth can afford to be more discriminating in its offers of tenure, it offers higher salaries to faculty, and the student body is one any high-quality faculty member would love to teach. And only teachers who love to teach undergraduates would be motivated to apply for a job at Dartmouth–for there are virtually no graduate students.

In the same breath, however, I would criticize the quality of a Harvard undergraduate education, where the student-to-faculty ratio is an ultra-low 6-to-1, but average class sizes are generally much larger, and graduate teaching assistants perform the overwhelming majority of grading and lead almost all the class discussions. To be graduate student at Harvard is to be on top of the heap; to be an undergraduate is fun an exciting, but the teaching is just not as good (see my post about a Harvard alumnus here).

In my next post, I’ll give you some ideas of questions you can ask admissions officers, faculty, and other administrators at colleges that will help you get a better sense of an institution’s priorities when it comes to teaching and learning.

Mark Montgomery
Great College Advice from an
Independent College Counselor

Published by Mark Montgomery

Mark is a leading educational consultant. His experience as a professor, college administrator, and youth mentor help him guide students from around the country and around the world.

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  1. Mark, I enjoyed your article, it brought up a lot of thought-provoking points. I have a question related to class cancellations based on “low” enrollment that you may be able to help me with. Is there a “typical” percent of classroom capacity used by colleges to determine whether or not to run a particular course section? I’m curious as to how my institution’s 75% figure compares to other schools, and what effect closing students out of courses late in the registration process has on student retention in a program. Thank you for the help.

  2. Hi, Jim.
    I’m not sure there is an industry wide standard on this. It’s interesting your institution’s rules are based on classroom capacity, not on other measures of demand. Apparently, if the rooms are filled and the facilities used to the maximum, that is the institutional definition of “success” at the registrar’s office. I think there may be other more budget-based guidelines at some schools: are there enough students in the course that we can justifying paying the faculty member to teach it? As for retention, I have little doubt that closing students out of important courses (or good courses) has some sort of impact on retention. But I don’t know of any studies offhand that corroborate that instinctive impression. Hope that helps in some small way. And sorry about the VERY late response to this question….ack!

  3. Mark, I really found your article on class size and student to professor ratios enlightening! My son is currently a senior in high school and we are looking at two larger schools, University of Illinois and Indiana, along with some smaller schools such as Miami of Ohio.

    He currently receives some 504 accommodations in high school but I think he will be OK on his own at college. I always thought he would do better in a classroom with a small student to prof ratio but your article made great sense about the quality of the professor regardless of the class size. I didn’t think about the possibility of a smaller class being an unpopular one or the professor teaching it-possibly a dud!

    I feel better about a Big 10 school being OK for my son in regard to the class size and it being more important to know the professor versus merely the class size. Thank you.

  4. Hi, Melissa, and thanks.
    Let me put it a different way. At a huge school, it is much more difficult for an undergraduate to get to know his or her professor. In a class of 250, how many kids will that professor know? If your son can advocate for himself and pushes hard to build a relationship, then a big class can be okay. For kids with LD of various sorts, however, this self-advocacy piece is really super important.

    Also keep this in mind: there are going to be professors who are lousy and professors who are great at all colleges. Your son must seek out the best teachers, not necessarily the best lecturers. Take a look at However, if your son does not generally do well in a strictly auditory environment, then large classes will not be good–no matter who the professor is.

    So there are many, many things to take into account here, and the decision is highly particular to each individual.

    Hope that helps. Thanks for taking the time to write in!

  5. Our primary criteria for college selection is the quality of the teaching learning experience, favoring highly interactive classes with facilitated discussion and the use of progressive and creative approaches to learning.
    We get precious little info from college search books, websites, etc about what really happens in classrooms. We are forced to use class size and ratios as proxies. Apparently the only way to find out is to enroll for a semester and see. Are there any resources that focus on the teaching / learning experience?

  6. Hello Pete,

    Very interesting question. I would suggest that you look at the College That Change Lives book and website. This is a group of schools that have been identified as offering a high quality academic experience. I would also encourage you to meet with professors when you visit colleges. You can find the email addresses for professors on most college websites.

    Katherine Price
    Senior Associate

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