Professional Learning

Does Class Size Matter? The Answer Is Yes

5 Min Read
Class Size Matters Hero

…But look closer; it’s not for the reason you’re thinking.

Researchers have come to a general consensus that smaller class sizes produce positive social, emotional, and academic results. Findings from numerous studies, including Glass and Smith’s class size research from 1978 and Tennessee’s Project STAR conducted in the mid 1980s, conclude smaller class sizes result in higher test scores, produce fewer dropouts, and level the playing field for minorities and children living in poverty.

Why Class Size Matters

On the surface, this all seems to be very good news. In fact, some will read no further than this and use the three assertions above as the backbone for far-reaching policies aimed at the reduction of class sizes. In fact, a passive knowledge of these findings has led many districts to push full steam ahead in an effort to reduce the number of children or increase the number of teachers in classrooms across the country. Sadly, a closer look at this research reveals that many administrative efforts to reduce class sizes or improve ratios are unlikely to bear fruit. This futility is not the result of poor intention, but rather lack of attention to the reality of the research. The truth easily reveals itself on closer inspection.

What’s the Ideal Student-Teacher Ratio? It’s Smaller Than You Think.

First, a closer look tells us that reductions from “extra large” class sizes to “large” class sizes won’t do the trick. Researchers generally agree a class size of no larger than 18 students is required to produce the desired benefit. You read that right—the ideal class size is 18 kids. Let’s face it; the dream of an 18-to-1 student–teacher ratio conflicts with the logistical and financial realities of many of our nation’s schools. Reducing class sizes to a max of 18 is not only improbable, but impossible for most. As such, school leaders who are working to reduce class sizes from 30 to 25, for example, are unlikely to see the academic bump they’re expecting.

When Does a Smaller Class Size Have the Biggest Impact?

A second look at the smaller class size research will also reveal that reduction in class sizes has the greatest benefit when applied longitudinally to grades K–3. This makes total sense, especially when you consider the foundational literacy and math skills children acquire at this age. So, what does this mean for school leaders? Well, it means if you’re a high school principal looking to reduce class sizes in order to see academic gains, you’re likely too late. Are smaller classes still a good idea? Yes. Would they have been a better idea 8 years before those kids arrived in the halls of your school? Absolutely. Districts would be better served focusing their energy and their resources related to class sizes on primary grades.

Do Smaller Class Sizes Make a Difference? Not Without Purposeful PD.

Look again. You’ll also find a reduction in classroom size produces no measurable or observable changes in teacher practices. The truth is, a teacher whose class goes from 30 to 20 is unlikely to change anything about his instruction as a result of the decrease. You would think such a reduction would lend itself to more individualized and personalized instruction. It does not. Individualization and personalization are the byproduct of an acquired skill-set that is cultivated through the addition of purposeful professional development; not the subtraction of students from a learning space. What does change however, is student behavior. Why? Because it is simply more difficult for students to hide undesirable behaviors when there are fewer kids in the room. It stands to reason that fewer opportunities for distraction will lead to more prolonged opportunities for attention.

So does class size matter? Of course it does; but not for the reason you’re thinking. Class size doesn’t matter because it changes teacher behaviors. Only PD and purposeful coaching can do that. Class size matters because it allows the teacher greater proximity to the students, and thus more opportunities for one-to-one and small-group instruction. The one constant in any room with smaller numbers of students is simply the proximity of the teacher to all of her students? That’s it.

What does this mean for us as educators? Well…it certainly doesn’t mean you should throw up your hands and jam 40 kids in a classroom because the reality of the research conflicts with the reality of your circumstances. We should continue to fight for classrooms with fewer students and more highly qualified teachers. What we can do is approach the conversation of class size with a collective understanding that any such initiative should also be accompanied by deliberate PD aimed at cultivating the individualization and personalization skills we desire.

Without that, all we are doing is moving kids from one place to another; and we don’t need a decade of research to tell us that won’t help kids.

The views expressed in this article are those of the author and do not necessarily represent those of HMH.


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