As American school officials debate when it will be safe for schoolchildren to return to classrooms, looking abroad may offer insights. Nearly every country in the world shuttered their schools early in the COVID-19 pandemic. Many have since sent students back to class, with varying degrees of success.

I am a scholar of comparative international education. For this article, I examined what happened in four countries where K-12 schools either stayed open throughout the pandemic or have resumed in-person instruction, using press reports, national COVID-19 data and academic studies.

Here’s what I found.

Israel: Too much, too soon

Israel took stringent steps early on in the coronavirus pandemic, including severely restricting everyone’s movement and closing all schools. By June, it was being lauded internationally for containing the spread of COVID-19.

But shortly after schools reopened in May, on a staggered schedule paired with mask mandates and social distancing rules, COVID-19 cases surged across Israel. Schoolchildren and teachers were among the sick. Today, several hundred Israeli schools have closed again.

Some blame lax enforcement of health guidelines in schools. The weather didn’t help: In May, a record heat wave hit Israel, making masks uncomfortable for students to wear.

But schools were only part of a broader reopening in Israel that, many experts say, came too soon and without sufficient testing capacity.

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“The reopening happened too fast,” said Mohammed Khatib, an epidemiologist on Israel’s national COVID-19 task force. “It was undertaken so quickly that it triggered a very sharp spike, and the return to more conservative measures came too little, much too late.”

Israel’s public health director, Siegal Sadetski, resigned in early July, saying the health ministry had ignored her warnings about reopening schools and businesses so rapidly.

Sweden: A hands-off approach

Schools never closed in Sweden, part of the Scandinavian country’s risky gamble on skipping a coronavirus lockdown. Only students 16 and older stayed home and did remote learning. Social distancing and masks were recommended but optional, in line with the Swedish government’s emphasis on personal choice.

This strategy earned praise from President Donald Trump but some resistance from Swedish parents, especially those whose children have health issues. The government threatened to punish parents who didn’t send their kids to school.

Sweden’s plan seems to have been safe enough. Its health agency reported on July 15 that COVID-19 outbreaks among Sweden’s 1 million school children were no worse than those in neighboring Finland, which did close schools. And pediatricians have seen few severe COVID-19 cases among school-age children in Stockholm. Only one young Swedish child is believed to have died of the coronavirus as of this article’s publication.

However, officials in Stockholm have admitted they don’t know how the disease may have affected teachers, parents and other adults in schools.

Sweden had over 70,000 COVID-19 cases as of July 21, which puts it in the middle of the pack in Europe, according to a joint study from Sweden’s Upsala University and the University of Virginia. Of those, slightly more than 1,000 involved children and teens.

Japan: So far, so good

Japan, which has mostly kept COVID-19 under control, took a conservative approach to reopening schools in June.

Different schools have different strategies, but generally Japanese students attend class in person on alternating days, so that classrooms are only half full. Lunches are silent and socially distanced, and students undergo daily temperature checks.

These precautions are more stringent than those in many other countries. Still, some Japanese school children have gotten COVID-19, particularly in major cities.

A survey from Save the Children found that Japanese school children wanted more clear and detailed information about the virus and the outbreaks. Parents, students and teachers continue to express hesitancy about returning to school and displeasure over reopening measures.

Uruguay: A+ for safety

Analysts credit Uruguay’s well-organized and efficient public health system and Uruguyans’ strong faith in government for its success stopping the coronavirus. The progressive South American country of 3 million has the region’s lowest rates of COVID-19 cases and deaths, and it never shut down its economy entirely.

Uruguay was one of the Western Hemisphere’s first countries to send its students back to school, using a staged approach.

In late April, Uruguay reopened schools in rural areas, where the student population is small. In early June, it brought vulnerable student groups, which were struggling to access online learning, and high school seniors back into classrooms. Then all students in non-urban areas went back to classrooms.

Finally, on June 29, 256,000 students in the capital of Montevideo returned to school. An alternating schedule of in-person and virtual instruction reduces the number of students in classrooms at one time.

Uruguay is notable for residents’ consistent and early adoption of measures like social distancing and masks. Its successful pandemic response comes despite its proximity to hard-hit Brazil, where schools remain closed.

Final grades

There is no perfect way to reopen schools during a pandemic. Even when a country has COVID-19 under control, there’s no guarantee that schools can reopen safely.

But the policies and practices of countries that have had some initial success with schools point in the same direction. It helps to slowly stage the reopening. Strict mask wearing and social distancing is critical, both in schools and surrounding communities. And both officials and families need reliable and up-to-date data so that they can continually assess outbreaks – and change course quickly if necessary.

That complicates school reopenings in the U.S., with its soaring COVID-19 cases, limited testing capacity and decentralized education system. Most countries have national education systems. In the U.S., school officials in all 50 states must sort through the same politicized messaging and confusing data as everyone else to make their own decisions about whether, when and how to welcome back students.

Bob Spires does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.