The U.S. has taken a different approach. As new cases climb above 100,000 per day, there are very few places in the U.S. where classrooms have remained full even as restaurants and bars are empty. In cities such as Boston and Washington, D.C., schools are remote, but indoor dining is allowed. This week, Detroit announced it was closing its schools through January, while indoor dining and bars there remain open at 50% capacity. Meanwhile, in states like Florida and Texas, schools — along with most businesses — have stayed open, even with very high and rising case rates.

Andreas Schleicher has a global view on education from his position in Paris overseeing the PISA international assessment program at the Organisation for Economic Co-operation and Development. He says that while schools in Europe were initially closed out of an abundance of caution, “Research has shown that if you put social distancing protocols in place, school is actually quite a safe environment, certainly safer than having children running around outside school.”

At the same time, he says that in Europe, “I do think people have understood fairly quickly how much damage the school closures have done, particularly to disadvantaged learners.” He says the science especially favors opening elementary schools, with young children both less likely to spread the disease and less able to benefit from remote learning.

Randa Grob-Zakhary of the group Insights for Education recently analyzed school reopening patterns across the world. When it comes to European countries, she says for the most part, “They have … localized closures based on numbers of cases.” For example, at Barve’s children’s school in Germany, sometimes just a single “pod” of about 20 children and teachers will be sent home to quarantine because of a case.

Johannes Huebner, the head of the pediatric infectious disease department at the Ludwig-Maximilians University Hospital in Munich, recently told NPR correspondent Rob Schmitz that scientific studies have not detected high rates of transmission in schools. “Most of the infections are brought into the schools by adults, by teachers, and then spread among kids. But most of the time, it’s only single cases. It’s two, three kids, five maybe that get positive.”

Grob-Zakhary says, “I think five, six months ago there was a view that we don’t know what the heck we’re dealing with and we better keep our kids safe no matter what. And now there’s a view that, yes, it’s dangerous, but we know so much more about how to handle it.”

Even where schools are open, it doesn’t mean everyone feels safe. In the U.K., teachers unions have raised safety concerns. And in Switzerland, one of the worst coronavirus hot spots in Europe, parent Anindita Basu Sempere is keeping her 6-year-old son home from school. It worries her that local health authorities don’t require children under 12 to wear a mask. She is seeking a doctor’s authorization to keep her son out of school as long as the current surge continues. She says her son is sad to be away from his friends, but he’s told her “it feels weird to not change what we’re doing when everything else is changing.”

President-elect Joe Biden has called school closures “a national emergency.” Some members of his newly appointed COVID-19 task force — including former Surgeon General Vivek Murthy, epidemiologist Michael Osterholm and oncologist and bioethicist Ezekiel Emanuel — have spoken cautiously in favor of reopening schools, but only with proper mitigation measures in place such as testing, contact tracing, social distancing and masking, which not all schools or locations have the resources to do currently. Murthy and Emanuel have written that schools should be open only where the virus is controlled.

Other American observers are adamant that the United States ought to make a different calculation of the societywide impact of school closures, even when virus spread is high. Dimitri Christakis, a pediatrician at Seattle Children’s Hospital and editor of the journal JAMA Pediatrics, has just published a paper that estimates 5.53 million years of life could be lost as a result of school closures in the United States.

The calculation is based on research showing that missing months of school lowers a child’s chances of graduating from high school. Lower educational attainment, in turn, is well established to lower life expectancy because people with less education are more likely to smoke, more likely to drink heavily, more likely to suffer from heart disease, and more likely to perform more hazardous work, among other reasons.

“When you frame it in terms of school versus lives, it becomes a no-brainer,” says Christakis. “And everybody says, ‘Well, we can’t send kids to school if it’s going to cost lives.’ But in fact, not sending kids to school also costs lives.”

Lala Tanmoy Das, an M.D.-Ph.D. student at Weill Cornell/Rockefeller/Memorial Sloan Kettering, is familiar with the kind of modeling Christakis used, and calls the paper “fairly robust.” But Das also points out that the virus is more dangerous for Black children, Latino children and those with preexisting conditions, and that we don’t know enough about its long-term effects on children or adults to capture the full impacts on health. He also notes that many school districts in the U.S. have faced budget cuts that make it hard to do mitigation measures, like regular disinfection, or put proper social distancing protocols in place.

Still, Das agrees with Christakis that schools shouldn’t be closed preferentially over other restrictions, particularly for younger children.