Large school districts across the country are reopening campuses to students, a slow-moving reversal driven by fear that students are falling behind and early evidence that schools have not become coronavirus superspreaders as feared.

It’s a major shift from the start of the year, when almost every big school system began fully online.

Trepidation about the pandemic persists. In many cities, coronavirus infection rates are rising, which could prompt school leaders to change their plans. Some classrooms and even entire schools have opened and had to close again in response to outbreaks. In some cities, opposition from teachers unions has slowed efforts to open buildings.

But overall, the trend is now toward more in-person school.

Of the 50 biggest school districts, 24 have resumed in-person classes for large groups of students, and 11 others plan to in the coming weeks, according to a Washington Post survey. Four more have opened, or plan to open, for small groups of students who need extra attention.

Many are in Florida and Texas, where Republican governors are requiring in-person classes, but schools are also open in New York City, Greenville, S.C., and Alpine, Utah, the state’s largest district. Returns are planned in Charlotte, Baltimore and Denver.

Just 11 of the largest 50 school districts are still fully remote, with no immediate plans to change that.

“I think everybody’s quite worried about what the price is that we’ve paid for having the buildings closed,” said Michael Casserly, executive director of the Council of the Great City Schools, a lobbying group for urban districts. He said the biggest drivers are concern about substantial “learning loss” and a sense that even though remote education is better than it was in the spring, it still is not working well enough.

Officials also worry because some students are simply not showing up to remote classes, with attendance figures down in many places.

Casserly said many educators fear that “we are going to dig ourselves a hole that is so deep that it takes us years and years to get out of.”

The trend is evident, too, in tracking by the Center on Reinventing Public Education at the University of Washington at Bothell. At the beginning of September, 24 of 106 mostly urban districts were open for at least some in-person school. By the end of October, that will rise to 69 out of 106, assuming districts stick with their announced plans.

“Parents are very, very eager to get their kids back to school. Students are very eager to get back to school,” said Robin Lake, the center’s director.

Assessing infection rates

In many districts, including in D.C. and its suburbs, students are being phased back into school, often starting with the youngest because online learning is so difficult for them. That’s also the approach in Charlotte-Mecklenburg Schools in North Carolina, which is using a hybrid system in which students are on campus on certain days and online on others.

Superintendent Earnest Winston said it’s the right move because children learn best in person, but he worries as he sees infection rates rising. For the first time since late July, the tally of newly reported coronavirus cases in the United States surpassed 64,000 last week. In 44 states and D.C., caseloads are higher than they were one month ago.

“This virus is still so new, things are changing rapidly, and so one thing that keeps me up at night is seeing this resurgence across the country,” Winston said. “I’m concerned we could move backward before we continue to move forward.”

But he is comforted that so far there is little evidence of significant transmission in school buildings.

A tracking project run out of Brown University, which includes data through early October from more than 1,200 schools, finds fewer than 1 percent of students and staff had confirmed coronavirus infections.

In Texas, which ordered schools to open, the Department of State Health Services reported nearly 2,000 students with newly confirmed cases for the week ending Oct. 11. That was a tiny fraction — well under 1 percent — of the 2.1 million students attending school in person. Among school staff, too, just a fraction of a percent reported infections.

And in New York City, the school system reported conducting more than 16,000 tests last week, with 28 people testing positive for the coronavirus — 20 staff members and eight students. That was just 0.17 percent of the total.

Data in other states is less clear because districts are not required to report cases. But overall, experts say, infection rates are lower than in the larger community.

It’s not entirely clear why, but experts say factors include mitigation strategies used by many schools, such as required masks and social distancing in the buildings, as well as children’s lower infection rates overall.

'We are losing them'

The learning losses during remote school have yet to be tallied, but they are believed to be significant for children in low-income families, who were already, as a group, academically behind. Data from an online math program called Zearn shows that students in high-income Zip codes have made more progress than is typical since January, meaning they used the program more than they normally would have, while those in low-income areas decreased their use, according to an analysis by Opportunity Insights, a research and policy institute based at Harvard University. Before the pandemic, high- and low-income students progressed through the program at similar rates.

“We are losing them,” said Atlanta Schools Superintendent Lisa Herring. “We have a responsibility to start to do as much as we can, as safely as possible, to not completely lose them before the close of this semester.”

Still, rising case counts persuaded her district to postpone the restart from later this month to January.

In Broward County, Fla., the schools have offered one of the most successful online education programs in the country, with years-long investment in online learning. But Superintendent Robert Runcie said in-person classes remain the gold standard. As in other districts in Florida, campuses in Broward are now open.

“There’s nothing good about being in the situation where we couldn’t open our schools,” Runcie said.

Some districts are starting small, with just a handful of students with special needs. In San Diego, elementary school teachers identified children struggling the most with online learning and invited them back into classrooms for lessons and special services, said Superintendent Cindy Marten. In-person classes for these students began last week.

“We like to say in our district, ‘If you can’t reach ’em, you can’t teach ’em,’ so let’s bring them in,” she said.

Marten said the district has taken precautions advised by a team at the University of California at San Diego, including keeping students six feet apart from one another, checking symptoms, placing dividers in classrooms, and setting up sanitation and hand-washing stations.

In some schools, too, she said, classrooms have been set up outside. “It is San Diego, after all,” Marten said.

There are no set dates for other students to return to school, she said, and there won’t be until the district sees how the limited program now underway goes. “It’s like we are crossing a fast-moving river and stepping on the first stone,” she said.

Open, then closed

In many parts of the country, schools have opened and then closed after coronavirus exposures.

New York City’s school district, the largest in the nation, became the first big-city system to reopen, with most of the 1.1 million students choosing to attend in person. Then some schools were forced to shut after cases spiked in ultra-Orthodox Jewish communities, where residents had ignored social distancing and other health protocols.

In Jefferson County, Ky., where Louisville is located, the school district has been planning to start reopening this week, but coronavirus cases are rising in the community, so that date probably will be pushed back, a spokesman said. Boston has opened classrooms for high-need students but delayed a phased reopening for others after virus rates rose in the city.

Other large districts have no plans to reopen. They include the country’s second largest, the Los Angeles Unified School District, which is offering in-person tutoring for some students but not regular school, and the third largest, Chicago Public Schools, where there is no in-person learning.

In Chicago, efforts to open buildings have run into opposition from the Chicago Teachers Union, which argues it would not be safe. The union’s complaint went to a formal arbitration, which the union won. The district is appealing. Meanwhile, the union is suggesting that it could strike if teachers are ordered back into classrooms.

In D.C., union pressures are also at work. The public schools plan to allow small groups of elementary school students back into classrooms next month, a total of about 7,000 students who are homeless, are learning English as a second language or have special education needs. Buildings also will be open to other students who will participate in remote school while being supervised by nonteaching staff.

The Washington Teachers Union had laid out a set of sweeping demands to return to in-person teaching, including hazard pay and an end to teacher evaluations. The teachers later dropped many of those demands, but they are insisting on some authority to help determine whether buildings have met a set of negotiated safety standards.

And in Baltimore County, Md., the school district plans to bring back students with physical and developmental special needs to four schools next month, but pressure from teachers may change that, said spokesman Brandon Oland.

“The teachers at those schools have been expressing their concerns, so I’m not sure what that’s going to mean for the plan,” he said. “What I’ve learned is the plan can change.”