Are smaller class sizes the key to breathing new life into today’s public schools, or a misguided effort to solve the problems of a dying era?

I am surprised to say I have come to believe it’s the latter.

First, let’s be clear: the arguments for reducing class size are well known, and have a well-established research base. As Leonie Haimson, the founding executive director of the New York-based Class Size Matters, has said: “There is robust research showing that smaller classes lead to fewer disciplinary disruptions as well as higher student achievement and engagement – in fact it is one of the few education reforms that has such robust research behind it and a multitude of proven benefits.” In one notable study from Tennessee, for example, which included 79 elementary schools and the random assignment of nearly 12,000 students, results showed that whereas all children in small classes did better on test scores, the gains for minorities were roughly twice that of white children, dramatically reducing the achievement gap.

Why is it that smaller class sizes lead to everything from higher test scores to lower disciplinary referrals? As Great Schools explains to prospective parents on its website, it’s “because there is a greater opportunity for individual interaction between student and teacher in a small class.” And as a similarly impressive set of research studies have shown, high-quality, high-trust relationships between adults and children are the foundation from which everything else in a healthy school must grow.

Another compelling argument for smaller class sizes comes from analyzing the current state of play in K-12 education. After all, it’s one thing to work in a school or system that prioritizes holistic child development and growth; it’s another to work towards that goal amidst a larger system in which child development is less valued than, say, higher test scores in reading and math. In the former, everything a teacher does or wants to do flows downstream, and is aided by the supportive currents of well-crafted policies. And in the latter, everything a teacher values most can only come from struggling against the current, and finding success through subversive practices.

In such a context, appealing for smaller class sizes is logical and important, and, in the short-term, it makes good sense.

If you take a longer view, however, there’s a subtle underlying assumption of both the research and the advocacy for smaller classes – and it’s one that unintentionally reinforces our fidelity to the Industrial-era model of schooling.

Think of it this way: if a teacher is at the front of the classroom, imparting a lesson to everyone, the only way he can do that in a more personal way is if there are less students in the room. And if a teacher is charged with corralling the individual attention and energy of a roomful of students, his efforts to impose discipline and order will only be aided by having less bodies to manage.

But what if we viewed school with a different set of guiding assumptions? What if, for example, the default mode of instruction didn’t depend on the transmission of knowledge via a single lesson? What if the philosophy of learning was that children should learn from one another as much or more than from any adult? And what if the model of discipline was not based on restricting a child’s movements, but on unleashing them?

In fact, these are the theoretical underpinnings of Maria Montessori, whose theories of child development have informed the creation of more than 22,000 schools around the world – and who, based on a set of assumptions about teaching and learning that diverged sharply from the Industrial-era transmission model, actually preferred larger class sizes, not smaller ones.

In her classic book The Absorbent Mind, Montessori, who was trained as a scientist and whose theories of learning were continually revised and revisited based on her direct observations of children, explained her rationale this way: “When the classes are fairly big, differences of character show themselves more clearly, and wider experience can be gained. With small classes this is less easy.”

The University of Virginia’s Angeline Lillard, a professor of psychology who has studied the extent to which Montessori’s century-old theories have been affirmed by 21st-century research, unpacks Montessori’s preference for large class sizes a bit further. “She believed that when there are not enough other children in the classroom, there are not enough different kinds of work out for children to learn sufficiently from watching each other work, nor are there enough personalities with whom children can practice their social interaction skills.”

“In traditional settings” in which class sizes are reduced, Lillard explains, “when one person is teaching the whole class simultaneously, that person would have more attention to devote to each child, and fewer children would conceivably allow for better teaching.” By contrast, “when children are learning from materials and each other, having more varied possible tutors and tutees, a greater variety of people to collaborate with, and more different types of work out (inspiring one to do such work oneself) might be more beneficial.”

In other words, smaller class sizes help increase the likelihood of better relationships, but they do so via a theory of teaching that no longer serves our purposes. Montessori schools (and schools like them) also create ample space for relational bonds to develop, but they do so via a theory of teaching that is aligned with what we now know about how people learn.

What should we expect in either case? A deeper investment in non-cognitive skills like persistence, motivation, and self-esteem; fewer disciplinary referrals; higher graduation rates; and greater levels of engagement and well-being.

The difference is this: whereas both approaches will improve our capacity to do all of the above in the short-term, only one requires us to radically alter the long-held assumptions we hold about teaching and learning. So let’s keep pushing for smaller class size – but let’s also start explicitly acknowledging its short-term value, and simultaneously demanding a wholesale revision of how we think about, evaluate, and define adult roles and responsibilities in our nation’s schools.

(This article also appeared in Huffington Post.)