Students wearing protective face masks amid the coronavirus disease (COVID-19) outbreak, clap along instead of singing a song during a music class at Takanedai Daisan elementary school, which practices various methods of social distancing in order to prevent the infection, in Funabashi, east of Tokyo, Japan July 16, 2020.

A shelf with books and games which could not be used by children is protected by tape in a classroom in a private school on the eve ot its reopening in Saint-Sebastien-sur-Loire near Nantes as France softens its strict lockdown rules during the outbreak of the coronavirus disease (COVID-19) in France, May 11, 2020.

Students wearing protective face masks sit in a classroom at D. Pedro V High School, as grade 11 and 12 high school students return to schools under strict restrictions, during the coronavirus disease (COVID-19) outbreak, in Lisbon, Portugal May 18, 2020.

Students wearing protective face masks respect social distancing as they walk past condemned lockers at the College Rosa Parks school during its reopening in Nantes as a small part of French shoolchildren head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 20, 2020.

Direction markers are seen on a stairwell before the students return to school in September, during the coronavirus disease (COVID-19) outbreak, at Larramendi school in Mungia, Spain, August 28, 2020.

A sign reading "Keep your distance" is seen above toilets at a primary school on the eve of its reopening in Nice as France softens its strict lockdown rules during the outbreak of the coronavirus disease (COVID-19) in France, May 11, 2020.

Green dots are placed in the schoolyard to help students keep distancing as schools outside the greater Montreal region begin to reopen their doors amid the coronavirus disease (COVID-19) outbreak, in Saint-Jean-sur-Richelieu, Quebec, Canada May 11, 2020.

Signs to maintain social disctancing between children are seen on the ground in the courtyard at a private school during its reopening in Saint-Sebastien-sur-Loire near Nantes as a small part of French children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 12, 2020.

First graders stand on marks for social distancing during a ceremony to mark the start of the new school year, amid the outbreak of the coronavirus disease (COVID-19) in Kyiv, Ukraine September 1, 2020.

A teacher talks to a girl, as other children sit in a classroom at a primary school, as Austrian schools reopen for pupils aged roughly six to 14, during the global coronavirus disease (COVID-19) outbreak, in Brunn am Gebirge, Austria May 18, 2020.

A student wearing a protective face mask amid coronavirus disease (COVID-19) outbreak, stands on a mark for social distancing at a classroom of Takanedai Daisan elementary school, which practices various methods of social distancing in order to prevent the infection, in Funabashi, east of Tokyo, Japan July 16, 2020.

Schoolchildren, wearing protective face masks, line up as they enter the primary school Simone Veil during its reopening in Nice as a small part of French children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 12, 2020.

A schoolchild and a teacher wear protective face masks in a classroom at a flemish primary school during its reopening as a small part of Belgian children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in Brussels, Belgium May 15, 2020.

Kindergarten students from the Wichuthit school eat their lunch during a rehearsal social distancing and measures to prevent the spread of the coronavirus disease (COVID-19) ahead of nationwide schools reopening in Bangkok, Thailand, June 23, 2020.

A student of Sam Khok school sits inside an old ballot box repurposed into partitions as she attends a class after the Thai government eased isolation measures and introduced social distancing to prevent the spread of the coronavirus disease (COVID-19), as schools nationwide reopened, at Pathum Thani province, Thailand, July 1, 2020.

Schoolchildren line up as they enter the primary school Simone Veil during its reopening in Nice as a small part of French children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 12, 2020.

Signs to help schoolchildren to respect social distancing are seen on stairs at a primary school during its reopening in Paris as a small part of Parisian children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 14, 2020.

A child wearing a protective face mask disinfects hands as she arrives at a primary school, while Austrian schools reopen for pupils aged roughly six to 14, during the global coronavirus disease (COVID-19) outbreak, in Brunn am Gebirge, Austria May 18, 2020.

Students practice social distancing in the courtyard at the College Sasserno school during its reopening in Nice as a small part of French shoolchildren head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in France, May 19, 2020.

Primary school pupils wear protective masks during their first day after the summer holidays, amid the spread of the coronavirus disease (COVID-19), in Belgrade, Serbia, September 01, 2020.

Students wearing protective face masks talk while practicing social distancing at the courtyard of the flemish secondary school during its reopening in Brussels, as a small part of Belgian children head back to their schools with new rules and social distancing measures, during the outbreak of the coronavirus disease (COVID-19), in Brussels, Belgium, May 15, 2020.

Director Juergen Scheuermann welcomes students as schools re-open after summer holidays and the lockdown due to the outbreak of the coronavirus disease (COVID-19) at the Karl-Rehbein high school in Hanau, Germany, August 17, 2020.

Children use hoops for social distancing at L'Ecole des Petits, an independent French bilingual school, as the coronavirus disease (COVID-19) lockdown eases in Fulham, London, Britain, June 9, 2020.

A teacher instructs pre-school children in proper hand washing during the first day in nursery school, after the reopening, amid the spread of the coronavirus disease (COVID-19) in Berlin, Germany, May 14, 2020.

Students wearing protective face masks stand on social distancing marks before entering a classroom at a francophone primary school during its reopening in Jumet, as a small part of Belgian children head back to their schools with new rules and social distancing measures, during the outbreak of the coronavirus disease (COVID-19), in Jumet, Belgium, May 18, 2020.

A child part of a small group aged between 6 to 10 years-old is seen in classroom at a nursery school, as part of a pilot test to see how social distancing can work in schools throughout the region of Piedmont, proposed by the mayor of Borgosesia Paolo Tiramani, during the coronavirus disease (COVID-19) outbreak, near Vercelli, Italy, May 12, 2020.

Employees install signs on the floor to help children to respect social distancing at a primary school on the eve of its reopening in Nice as France softens its strict lockdown rules during the outbreak of the coronavirus disease (COVID-19) in France, May 11, 2020.

A student wearing a protective face mask uses hand sanitizer upon arrival at D. Pedro V High School, as grade 11 and 12 high school students return to schools under strict restrictions, during the coronavirus disease (COVID-19) outbreak, in Lisbon, Portugal May 18, 2020.

Children listen to the school director's speech during the first day of a new school year, amid the coronavirus disease (COVID-19) outbreak, in Warsaw, Poland September 1, 2020.

A teacher takes the children's temperature at the entrance of a flemish primary school during its reopening as a small part of Belgian children head back to their schools with new rules and social distancing during the outbreak of the coronavirus disease (COVID-19) in Brussels, Belgium May 15, 2020.=