Sunday, April 10, 2011

Class Sizes

I have read some of the research that says that class sizes don't effect learning outcomes substantially and I just don't believe it. I have taught school off and on from 1971, in public schools, in private schools, in charter schools. I have taught in inner city schools with racial problems, in rural schools, in relatively wealthy suburban schools. I have taught and subbed in 4 widely differing states (Massachusetts, Illinois, Colorado, and Alaska). I have subbed in classes of 15 students and taught classes of 35 students. From what I see, numbers make a difference. There seem to be several major ways that numbers make a difference: discipline, content, ability to differentiate, personal connection.

No matter how well-trained a class is, 35 students inevitably are harder to organize than 15. Just figuring out where to put all the desks/tables/chairs is a huge logistical task for a class with 35 students. And young people are not miniature robots, or, for that matter, miniature adults. They haven't yet learned all of the social behaviors that adults can usually manage to bring forth in large group situations.

Part of getting students involved in their own education is to make a personal connection of what they are learning to what they already know and ways that they can use the new knowledge in their lives. If you are trying to have a personal conversation with 15 students about this, it is possible to touch on each of the students in the group. With 35 students, you have to have recourse to other methods - e.g., dividing up the group into smaller sub-groups, then reporting back to the whole group. With 15 students, you can alter the content of the lesson to address particular facets of the topic that impact members of the group. With 35 students, this is rarely possible.

In the many years that I subbed, about 8 years, I only ran across one teacher who
tried to individualize students' learning completely. I don't know how successful she was, but as a sub, it was extremely difficult. But not all of the students in any given class are in the middle of the ability/readiness range for the lesson. There are ALWAYS some outliers, ones who may already know the "new" material and ones who haven't yet mastered the prerequisites. With a class of 15, it is possible to individually support both ends of the outlier spectrum. With a class of 35, it is rarely done. Yes, teachers are taught about differentiation in college, yes, they say they understand how to do it; no, I don't see them actually doing it. It is simply too hard. Imagine a college professor teaching chemistry. Do we give him/her a class that needs to cover elements and atoms, acids and bases, all the way through to quantum mechanics? Of course not, that would be absurd. We set up a general sequence of learning chemistry and apportion the students into classes based on what they each need to learn next. Yet, we give an elementary school teacher 25 to 30 students, some of whom can barely read and some of whom are reading 4 or 5 grade levels above their nominal grade placement. With 15 students, and say 3 sub-groups, it is possible to reach more children than with 25 students. It is also a matter of simple math. If I have 50 minutes with 15 students, 20 minutes of which is spent in whole group instruction, there is a possibility of 2 minutes per student of individual help. With 30 students, there is 1 minute. How much can you get done in 60 seconds?

In a class of 15 students, a teacher can really get to know the students. With 30, it is much more difficult. That personal connection between teacher and student is what makes much of teaching and learning intimately fulfilling. Without it, teachers begin to feel like simple curriculum delivery vehicles and students begin to feel like insignificant cogs in the information factory.

Years ago, I read a research report that consolidated observations from different sized classes, from tiny classes of 6 or 7 through huge classes of 50 or 60. From what I remember, there seemed to be several breaking points in class size and class dynamics. With extremely small classes, children often had trouble finding kids who were similar to them in learning stage. At 12 to 15 students, there seemed to be change in classroom dynamic - enough diversity for different types of interactions depending on learning activities. Class dynamics changed again around 18 to 24 students, with more whole group instruction and fewer individually tailored assignments. With 25 or more students, the classes were largely given over to whole group instruction and standard assignments. There was some support for students with difficulties, but little or no accommodation for students who already knew the material. I would love to find that research again, but haven't been able to locate it.

The politicians now are bent on cutting funding for education and class sizes almost certainly will increase in many schools across the country. I can't help but feel this will make teachers jobs even more difficult than they already are. I suppose, if the research study above is correct, increasing class sizes from 25 to 30 students might not substantially change how the classroom functions. It does substantially increase teacher work load - but what do the politicians care about that - teachers have a long summer vacation to recover.


  1. I do believe that it *CAN* make a difference, but my daughter has been in small classes where the small class size has *Not* made a difference. The teacher taught just the same as she would have to a class of 35.

  2. But that is the case with any modification of a standard. The question really is whether over a large number of classrooms, with different teachers, different students, different schools, different curricula, does it make a difference. I would contend that there are some teachers who would teach no differently, but that there would be a significant number who would take advantage of smaller classes by teaching what I would consider to be "better". This could be furthered by a modicum of training - or simply encouragement to use what many new teachers are learning in colleges these days - differentiation. They are learning it, but finding it extremely difficult to implement in large classrooms, so they revert back to the tried and true standards that they learned by (and often that their parents and even grandparents learned by).