When leaders at Megan Claffey’s Colorado district decided to give parents a choice between online and hybrid learning, they didn’t expect many to choose the all-online option. But instead of the 100 or so families they had planned for, more than 2,800 opted to keep their kids home full time. Without an influx of new teachers, Claffey and her colleagues were left scrambling to adjust.
“Part of it is that they just were not prepared, I guess, for that many people to say that they wanted to be online,” says Claffey, who teaches third grade. “So the day before teachers were called back, I got a call from my principal asking me to go online.”
In addition to the challenge of quickly adapting her teaching, Claffey also encountered an unexpected frustration: a class size of 60, featuring students from every elementary school in the district, which was later reduced to around 50 as new teachers were added. Despite sorting students into groups based on reading ability and spending extra hours combing through various data dashboards, she is still adjusting to the demands of teaching so many students at once.
“As a teacher, I don't feel like I'm doing the best work I can,” Claffey says. “I don't feel like I can give them what I could give them in the classroom as far as individual attention and differentiated lessons. I’m doing my best, but sometimes kids just need that one-on-one time.”
Claffey’s is hardly an isolated case. In New York City, schools can now double the in-person limit of 34 students per class when it’s all online. From Rhode Island to Arizona, families and teachers complain of online class sizes that routinely creep past 50 students. And elsewhere, parents are taking note of swelling online classes in districts where socially-distant, in-person classes hold as few as 13 students.
Yet much like the debate over the appropriate length of a remote school day, Claffey and others are asking a single, pressing question of administrators, fellow educators and even social media communities: Where are these numbers coming from?
“Where are they getting the research to say, ‘Here's 50 kids for one teacher’?” Claffey says. “What does the research say on that?” So far, she says, she hasn’t received a good answer.
When it comes to research, part of Claffey’s dilemma may stem from the fact that not much has been conducted on the topic at the K-12 level (most has focused on online class sizes in higher education.) And the limited research that is out there is hardly prescriptive.
According to one 2018 paper, led by Chin-Hsi Lin at the University of Hong Kong, “there is no one-size-fíts-all solution to the ideal class size question.” Instead, Lin and his co-authors contend that various environmental factors, such as teacher experience and the subject being taught, should help determine class size. When classes require a dense amount of collaboration between students, for example, smaller class sizes of around 15 students are preferable. In a separate study, Lin used models to determine that students’ final grades began to suffer once class sizes reached 45 students—a number he uses as an upper limit.
“The context was different from what teachers are experiencing right now,” explains Lin in an interview. “Teachers are using synchronous learning [now], but I think findings can be applied to the current situation.” Here, he points to a finding that extreme class sizes—in either direction—can be detrimental to student learning. If classes are too small, say 5-10 students, classroom discussion and group work may be more difficult. Yet in larger classes, teachers will find it difficult to give attention to every student, especially if they teach upper grades and have multiple classes and hundreds of students overall.
Really, Lin says, a better rule of thumb for schools may be to keep online class sizes level with the traditional sizes teachers are used to. “If 20 is a normal class size in face-to-face settings, I would say keep that the same.”
Over the past two decades, researchers have paid the most attention to online charter schools and state virtual academies regarding online class sizes. A 2019 paper from the National Education Policy Center found that most virtual academies have class sizes much larger than those found in traditional public schools—nearly three times as many or about 44 students to a teacher.
While other factors are surely at play, the same paper noted the “body of evidence is overwhelming in its critical conclusion that virtual schools are performing terribly with no signs of improvement.” As part of its recommendations, the authors suggested reducing student-teacher ratios, and suggested that district-specific virtual programs with smaller class sizes are likely to see better outcomes.
Falling Between the Cracks
By and large, administrators in New York and elsewhere report that larger online class sizes are a necessity given the need to allocate enough teachers to keep in-person classes small and the difficulties in finding substitutes during the pandemic. Other times, supersized classes may be the result of administrative or logistical challenges.
“We’re putting out fires and not planning for success,” says Jessica Camacho, whose English language learning classes in Cedar Rapids, Iowa, have shot up from her usual 30 to somewhere between 43 and 46 students. “I think a lot of that comes from the need to plan at the district level without input from the people that have their boots on the ground, so they’re missing super important parts of teaching kids.”
At Camacho’s district, where families were given a choice of virtual and hybrid options, teachers who had health concerns were given priority for online teaching. “Many times those are the ones that are teaching online, but that doesn’t mean that you have the most effective online teachers.”
Between the large class sizes, families on the margins of poverty, and spotty internet access among the students she teaches, “there definitely could be kids that are falling between the cracks,” she adds.
Another point in favor of keeping class sizes as low as possible: student perception. Lin did not use this metric in his research, but it’s an important factor overall. “Who wants to be in a large class size? Nobody,” says Lin. “Every student wants their teacher’s full attention. It may not affect their online performance for high-performing students but I wouldn’t recommend it.”