When asked, teachers and parents tend to prefer smaller class sizes over larger ones. But life requires choices, and school finance decisions always involve trade-offs. The debate over class size is no different. Researchers have consistently found a tension between hiring more teachers, on the one hand, and, on the other, paying existing teachers more money.
The New York Legislature this week ignored these trade-offs. In a deal to extend mayoral control over New York City schools, legislators also passed legislation requiring the city to adhere to strict limits on class sizes.
Reducing class sizes might be a politically popular move at the moment, especially in response to the large academic losses students suffered thanks to the COVID-19 pandemic. U.S. Secretary of Education Miguel Cardona has also touted smaller class sizes as a way to remedy lost instructional time.
However, the best available research on class size suggests a more nuanced story. Large-scale reductions in class size have been linked to improved student outcomes, but more incremental efforts — like what New York is proposing — have had no discernible effect. Moreover, the gains from small class sizes have been concentrated among younger students. It’s not a solution that’s well-suited to helping middle or high school students.
Class size reductions are also tremendously expensive compared to other potential investments. City leaders estimate the proposed changes would cost the city at least $500 million a year, and that number doesn’t include all the grades affected or the cost of additional space. That’s money that can’t be used for other things — such as extracurriculars or counselors or higher salaries.
For any policy, there’s also a question of timing and when it’s being implemented. A new, state-imposed class size reduction would force the city to hire many more teachers soon, likely in the midst of a challenging labor market. New York schools are already reporting staff shortages, particularly among special education and STEM teachers, and the unemployment rate for college-educated workers is back to its pre-pandemic lows. It’s a tough environment to add lots of staff.
Historically, when districts are faced with tight labor markets, they have to go deeper into the labor pool and as a result tend to hire less effective teachers. It might sound good for students to share their classes with fewer peers, but not if it means fewer kids have access to effective teachers. Those two things can more than cancel out.
These trade-offs are not merely abstract. A research study on an earlier effort to reduce class sizes in New York City attempted to balance the positive benefits of smaller classes with the harms caused by a greater number of newly hired teachers from a stretched labor pool. The author concluded, “class size reduction can substantially improve student achievement if teacher quality is held constant. When teacher quality is not held constant, however, class size reduction is unlikely to generate large improvements in student achievement.”
The class size bargain can be a particularly bad deal for low-income students. When schools are forced to hire a lot of inexperienced teachers, who do those rookie teachers end up serving? One study from a similar effort in California found it was mainly Black, Hispanic and low-income students who were taught by the least experienced and least qualified teachers.
The state’s proposal would also constrain the city’s budget in overly restrictive ways. For example, the bill would lower the maximum class size for each classroom, rather than setting an average and letting school leaders manage individual assignments. This year, the average kindergarten class in the city has 20.1 students. Under the new law, an elementary school with 60 kindergarten students could have three classes of 20 students each, but if even one more 5-year-old enrolled, the school would be forced to split its students into four classes and hire an extra teacher. (The legislation creates narrow exceptions to the mandate, but these don’t include common sense.)
Parents, teachers and school leaders would likely prefer a less rigid policy. Surveys reveal different preferences once people are given true apples-to-apples comparisons. For example, when asked if they’d prefer their child have a smaller class taught by a randomly chosen teacher, or a larger class taught by one of the district’s best teachers, the vast majority of parents picked the larger class with the better teacher. Similarly, when teachers were given a cost-equivalent choice of a $5,000 raise or reducing class sizes by two students, the vast majority said they would prefer the extra money.
Unfortunately, the class size debate is often reduced to a simple yes or no. The truth is that smaller classes can help in some cases, but they may not work as well — and can even backfire — in other circumstances. The across-the-board caps the state wants to impose upon the city are a bad idea.
This commentary was published June 3, 2022 in the New York Daily News.