Most U.S. school districts suspended in-person instruction during the COVID pandemic that struck the nation during late 2019 and early 2020. Many districts transitioned to remote or hybrid modes of instruction during the winter of 2020. Since most districts that switched from in-person instruction were neither experienced with nor effectively trained to implement the virtual learning modes they resorted to, reports of extensive student absences, passive student participation and extensive student learning loss quickly accumulated. Estimates vary about the quantity and quality of the learning loss students experienced, and how long it might take to remediate the resulting damage.

While schools were closed, districts developed plans for when and how they should reopen. Districts carried out those plans in the spring of 2020, and many subsequently implemented special summer sessions to try to recuperate their students’ learning losses. In the 2020-21 school year, many districts resumed in-person instruction, while other districts opened virtually, provided hybrid options or remained remote throughout the school year. Some smaller districts never closed or switched from in-person to other instructional modes. This range of schooling responses to the pandemic generated a research stream analyzing the variety of school district decisions and the patterns underlying the choices districts made.

This initial research suggested that density (urban, suburban or rural populations), demography (particularly race/ethnicity and socio-economic class), and what researchers called partisanship (the extent to which districts voted Democrat or Republican) were primary factors associated with districts’ choice of when and how to reopen, once the initial COVID onslaught began to subside. The early research indicated that rural and Republican-leaning districts were more likely to return to in-person instruction, while urban, more Democratic districts were more likely to implement virtual or hybrid modes. Consistent with these factors, research suggested that advantaged parents in more White and affluent districts tended to opt for in-person instruction because they perceived the risks of student infection in schools as relatively minor, compared to the advantages of such instruction. Low-income Black and Latino parents in dense urban districts tended to be more resistant to in-person learning because of their perceptions of potentially serious health risks to students and their families through such instruction.

In the pandemic’s early period, before vaccines had been developed or effective PPE had been equitably distributed, essential workers, predominantly people of color working in hospitals, other health care institutions, fire and safety services, transportation, food preparation and distribution bore the brunt of the pandemic’s infection rates, hospitalizations and deaths. Keeping their children home rather than in schools and thereby reducing student and family exposure to COVID became a necessary decision for many parents who also served as essential workers.

A second wave of research about COVID and education focuses on the complexity of how and when school districts chose to reopen their schools. This research analyzes how districts tried to balance their duty to protect students, various school staff, and their families from the pandemic’s ravages with the need to maximize their students’ learning opportunities. Both a qualitative and a quantitative study from the Annenberg Institute for School Reform (AISR) at Brown University, for example, complicate the early findings. The qualitative study, by Jeremy Singer, Julia A. Marsh, David Menefee-Libey, Jacob Alonso, Dwuana Bradley and Hanora Tracy, focuses on the reopening choices made by five large urban school districts–Denver, Detroit, New Orleans, Portland (Oregon) and the District of Columbia–after the devastating first COVID wave in the winter of 2020. That study found that decisions to reopen schools in those districts were strongly influenced by public health guidance, union-district relations and labor market dynamics.

The qualitative AISR study found that national school health guidelines from the federal Centers for Disease Control and advice from state health centers played major roles in shaping district decisions about reopening. Superintendents and district administrators relied on such guidance as well as on data detailing district rates of COVID infection. City and state leadership also played key roles – the Oregon governor and the District of Columbia mayor ordered the closing and reopening of their schools. Union pressure to protect teachers, students and their parents played a critical role in Detroit, where the teachers’ union threatened to strike unless district leadership ensured vital health protections for students and school personnel. The Detroit teachers’ union also negotiated an agreement with the district to allow teachers to choose whether to teach virtually or return to in-person classes. In the other four districts, the teachers’ unions played more limited roles. Finally, the study found some evidence that local charter schools’ reopening decisions largely echoed the actions of their encompassing public districts.

The quantitative AISR study analyzed the COVID-related decisions of more than 600 school districts across Ohio during the 2020-21 school year. State authorities gave districts considerable flexibility to develop reopening plans and provided them with critical data about the pandemic’s progression to help inform their decisions. In early July 2020, the state established the Ohio Public Health Advisory System, which reported COVID-related health data including the number of new cases and information about emergency room visits, hospital admissions, and intensive care unit bed occupancy. When schools opened in the fall of 2020, staff and parents of students were required to notify schools if they or their children had tested positive for COVID. Schools had to report these cases to their local health department within 24 hours, which in turn reported them to the Ohio Department of Health. The state’s Department of Education also recorded the instructional mode adopted by each Ohio school district each week , and published these data online beginning in mid-September 2020.

The AISR quantitative study, led by Alvin Christian, Brian Jacob and John D. Singleton found that decisions about district closings and reopenings were primarily related to increases in COVID rates of infection during the previous week. Both studies found that the opening and closing decisions of peer and neighboring districts also influenced their own choices to reopen. Curiously, the qualitative study indicated that school district leadership , -primarily superintendents-were the primary decision-makers about openings and closings, with their school boards playing supportive roles. The quantitative study attributed critical decisions about when and how to reopen to district school boards.

A new study from Thomas Kane and associates at the Harvard Graduate School of Education also complicates the early research findings. Addressing the issue of how much remote learning contributed to students’ learning losses, Kane’s team found that districts that stayed remote during the 2020-21 school year experienced bigger declines in students’ elementary and middle school math outcomes, and to some extent in reading, than other districts in their states. But the losses varied widely; many districts that resumed in-person instruction sustained bigger losses than districts that stayed remote. The study found such extensive variation in student outcomes that it suggested that remote instruction was not the primary driver of the considerable learning loss the pandemic imposed on the nation’s students.

Another new study found that maintaining masking requirements in district schools is associated with decreases in COVID rates of infection among district students. Taking advantage of a natural experiment after Massachusetts lifted its student masking requirement, all but two school districts (Boston and Chelsea) in the greater Boston area ended masking in the spring of 2022. But the state continued to require districts to monitor and report data on all COVID infections in schools.

The study’s researchers, led by Tori L. Cowger, the study’s first author and a postdoctoral fellow at the Harvard T.H. Chan School of Public Health, used that data to compare COVID transmission rates and school time lost to the pandemic in districts that either terminated or continued masking requirements. The study found that removing mask mandates in districts was associated with an additional 44.9 COVID cases per 1,000 students and staff members, corresponding to an estimated 11,901 cases during the 15-week period after the state ended its masking requirement. Because students and teachers testing positive for COVID had to isolate for at least five days, the researchers calculated that additional COVID cases in the unmasked districts led to at least 17,500 missed school days for students and 6,500 missed school days for staff. COVID infection rates were lower in Boston’s schools, long plagued by aging, crowded buildings with poor ventilation, than among unmasked students attending newer schools in affluent communities like Cambridge and Newton.

This study has several limitations; it is correlational rather than randomized. It doesn’t account for variations in how districts implemented their post-masking policies. And it doesn’t speak to how districts might mitigate the ways that masking limits the communication essential to effective teaching and learning. But it does suggest that research analyzing variations in school districts’ responses to the COVID pandemic can generate very useful findings.

Such studies can tap the data generated by districts’ variable responses to the pandemic to develop findings that might clarify impassioned but relatively uninformed debate about, for example, the merits of masking. Studies about districts’ choice of instructional mode might clarify which categories of students are best or ill-served by in-person, virtual or hybrid modes of instruction. Evidence from some initial studies indicate, for example, that incidences of bullying were much reduced in districts implementing remote instruction, for obvious reasons. Other studies show that some categories of students with disabilities were effectively served by remote instruction, while students with other categories of disability suffered severe learning loss. Studies of districts with high percentages of English Language Learners indicate that such students are similarly poorly served by remote instruction. Other studies suggest limited results of remote instruction for students in temporary housing or for long-term absentee students.

Carefully targeted research can help determine the categories of students effectively or poorly served by the modes of instruction districts implemented during the pandemic. Ultimately, such studies can inform us about what instructional policies school districts should implement to best protect students, various school staff and their families from future pandemics while reducing the student learning losses that such protective policies imposed during the COVID pandemic. Such research can help us prepare far more effectively for the coming pandemics we will undoubtedly face.