An ongoing struggle to fill teaching positions has some educators concerned about an effect on class sizes in Connecticut's schools.

Connecticut, like much of the country, has experienced a notable teacher shortage in recent years, with about 1,300 vacancies statewide this fall. In response, school districts have ramped accelerated recruitment efforts, paid teachers extra to take on additional periods and often relied on long-term substitutes to fill gaps.

In some cases, educators say, districts have also collapsed classes together, asking fewer teachers to instruct more students. Class sizes, which are often capped in union contracts, tend to be largest in poor, urban districts, where staffing issues have been most acute in recent years.

"Class size in an urban district has always been a concern, and that concern has been aggravated since the pandemic," said Carol Gale, president of the Hartford Federation of Teachers.

Due to a lack of data, it is difficult to assess exactly what class sizes look like in Connecticut or how they have changed in recent years. The state, which collects thorough data on a wide range of education-related subjects, doesn't track class sizes, and some school districts reached by CT Insider said they don't have reliable numbers either.

But educators and advocates say they've seen class sizes grow in certain places, and some districts acknowledge an uptick. In New Haven, the average class size across all classrooms is up district-wide from 17.9 students per classroom in 2022-23 to 19.6 in 2023-24, a spokesperson said.

The issue is often particularly pressing in areas such as special education where districts have had an especially difficult time finding teachers.

"Here in New Haven, our continued concern is our class sizes and caseloads for special education teachers," said Jennifer Graves, a longtime special education instructor in New Haven who is now a union leader there. "The number of students needing specialized instruction and programming is just increasing every year, making it extremely difficult to deliver intensive interventions."

Though the lack of state data makes it difficult to compare districts against each other, those close to the issue say it's worst in lower-income districts, which often struggle to pay teachers competitive salaries.

"For the most part, it is in our most challenged districts, where there is the greatest shortage of teachers," said Fran Rabinowitz, executive director of the Connecticut Association of Public School Superintendents.

Research has regularly found that large class sizes can hurt student performance, harming classroom engagement and reducing attendance.

Alyssa Hadley Dunn, director of teacher education at the University of Connecticut, said school districts should generally aim to keep classes as small as possible.

"We have decades of research that shows small class sizes matter," she said. "It matters for teachers, it matters for students, it matters for families, it matters for academic outcomes and socio-emotional learning outcomes."

Kate Dias, president of the Connecticut Education Association, the state's largest teachers union, said large class sizes can pose practical issues, stretching a classroom's physical space. But more importantly, she said, they limit the kind of instruction a teacher can provide.

"There's a finite number of minutes in a day, and a teacher is trying to distribute their attention to all their students in their room," Dias said. "And every student you add to a space subtracts time from another student."

In Rabinowitz's experience, including as an elementary school teacher, large class sizes can also lead to behavioral and disciplinary issues for students.

"Many of our children come with some emotional baggage, but if I had 15 kids in a class, I could work with that, and I would have more time and strategies to work with every child in my classroom no matter what their need was," she said. "At 28 [students], it's pretty overwhelming to meet everyone's needs."

Over recent years, administrators across Connecticut have wrestled with difficult filling teaching positions, as burnout among educators and growing needs among students create a gap between the supply of educators and the demand for them. In some districts, this has meant hiring less qualified teachers. In others, it has meant asked staff to do more or leaving classes without a full-time instructor.

In Stamford, administrators have taken pains to avoid increasing class sizes, chief academic officer Amy Beldotti said. Instead of adding more students to a given class, she said, the district has offered middle- and high-school teachers extra pay to teach additional sections of their classes.

"We've gone sort of a different route," Beldotti said. "So we have not seen a real change in our class sizes since the teacher shortage."

Julia Skrobak, a spokesperson said for Hartford Public Schools said that district also hasn't seen an increase in class sizes, maintaining an average of 20-22 students per section in recent years. In some cases, she said, the district has moved teachers from one building to another to cover gaps and avoid having to increase the number of students in each class.

Overall student enrollment in Connecticut schools has dropped since the start of the COVID-19 pandemic, state data shows, which may be alleviating pressure to increase class sizes in some districts.

As of 2018, the average self-contained Connecticut elementary classroom had 19.4 students, while the average high school class had 21.5, according to the National Center for Education Statistics.

School district officials warn that data around class sizes can be difficult to collect and measure, since students come and go throughout the school year and some are instructed in specialized classes, which can skew averages.

Timothy Grasty, a representative of the Bridgeport superintendent's office, said the district could not provide accurate numbers, for those reasons.

"We haven't been able to gather that information because it fluctuates so often throughout the school year," Grasty said. "There are so many variables that would affect it."