In early 2020, as the coronavirus spread, schools around the world abruptly halted in-person education. To many governments and parents, moving classes online seemed the obvious stopgap solution.

In the United States, school districts scrambled to secure digital devices for students. Almost overnight, videoconferencing software like Zoom became the main platform teachers used to deliver real-time instruction to students at home.

Now a report from UNESCO, the United Nations’ educational and cultural organization, says that overreliance on remote learning technology during the pandemic led to “staggering” education inequality around the world. It was, according to a 655-page report that UNESCO released on Wednesday, a worldwide “ed-tech tragedy.”

The report, from UNESCO’s Future of Education division, is likely to add fuel to the debate over how governments and local school districts handled pandemic restrictions, and whether it would have been better for some countries to reopen schools for in-person instruction sooner.

The UNESCO researchers argued in the report that “unprecedented” dependence on technology — intended to ensure that children could continue their schooling — worsened disparities and learning loss for hundreds of millions of students around the world, including in Kenya, Brazil, Britain and the United States.

The promotion of remote online learning as the primary solution for pandemic schooling also hindered public discussion of more equitable, lower-tech alternatives, such as regularly providing schoolwork packets for every student, delivering school lessons by radio or television — and reopening schools sooner for in-person classes, the researchers said.

“Available evidence strongly indicates that the bright spots of the ed-tech experiences during the pandemic, while important and deserving of attention, were vastly eclipsed by failure,” the UNESCO report said.

The UNESCO researchers recommended that education officials prioritize in-person instruction with teachers, not online platforms, as the primary driver of student learning. And they encouraged schools to ensure that emerging technologies like A.I. chatbots concretely benefitted students before introducing them for educational use.

Education and industry experts welcomed the report, saying more research on the effects of pandemic learning was needed.

“The report’s conclusion — that societies must be vigilant about the ways digital tools are reshaping education — is incredibly important,” said Paul Lekas, the head of global public policy for the Software & Information Industry Association, a group whose members include Amazon, Apple and Google. “There are lots of lessons that can be learned from how digital education occurred during the pandemic and ways in which to lessen the digital divide.”

​Education International, an umbrella organization for about 380 teachers’ unions and 32 million teachers worldwide, said the UNESCO report underlined the importance of in-person, face-to-face teaching.

“The report tells us definitively what we already know to be true, a place called school matters,” said Haldis Holst, the group’s deputy general secretary. “Education is not transactional nor is it simply content delivery. It is relational. It is social. It is human at its core.”

Here are some of the main findings in the report:

The promise of education technology was overstated.

For more than a decade, Silicon Valley tech giants as well as industry-financed nonprofit groups and think tanks have promoted computers, apps and internet access in public schools as innovations that would quickly democratize and modernize student learning.

Many promised that such digital tools would allow schoolchildren to more easily pursue their interests, learn at their own pace and receive instant automated feedback on their work from learning analytics algorithms.

The report’s findings challenge the view that digital technologies are synonymous with educational equality and progress.

The report said that when coronavirus cases began spiking in early 2020, the overselling of ed-tech tools helped make remote online learning seem like the most appealing and effective solution for pandemic schooling even as more equitable, lower-tech options were available.

Remote online learning worsened education disparities.

UNESCO researchers found the shift to remote online learning tended to provide substantial advantages to children in wealthier households while disadvantaging those in lower-income families.

By May 2020, the report said, 60 percent of national remote learning programs “relied exclusively” on internet-connected platforms. But nearly half a billion young people — about half the primary and secondary students worldwide — targeted by those remote learning programs lacked internet connections at home, the report said, excluding them from participating.

According to data and surveys cited in the report, one-third of kindergarten through 12th-grade students in the United States “were cut off from education” in 2020 because of inadequate internet connections or hardware. In 2021 in Pakistan, 30 percent of households said they were aware of remote learning programs while fewer than half of this group had the technology needed to participate.

Learning was hindered and altered.

Student learning outcomes stalled or “declined dramatically” when schools deployed ed tech as a replacement for in-person instruction, the UNESCO researchers said, even when children had access to digital devices and internet connections.

The report also said students learning online spent considerably less time on formal educational tasks — and more time on monotonous digital tasks. It described a daily learning routine “less of discovery and exploration than traversing file-sharing systems, moving through automated learning content, checking for updates on corporate platforms and enduring long video calls.”

Remote online learning also limited or curtailed student opportunities for socialization and nonacademic activities, the report said, causing many students to become disengaged or drop out of school.

The report warned that the shift to remote learning also gave a handful of tech platforms — like Google and Zoom — extraordinary influence in schools. These digital systems often imposed private business values and agendas, the report added, that were at odds with the “humanistic” values of public schooling.

Regulation and guardrails are needed.

To prevent a repeat scenario, the researchers recommended that schools prioritize the best interests of schoolchildren as the central criteria for deploying ed tech.

In practical terms, the researchers called for more regulation and guardrails around online learning tools. They also suggested that districts give teachers more say over which digital tools schools adopt and how they are used.