Students wearing face masks attend a class at Al Mrooj School in Jubail, Saudi Arabia, on Aug. 29, 2021. Saudi Arabia's students came back to school on Sunday, starting their new academic year after receiving 17 months of online education. Only fully vaccinated students aged above 12 can return to school, while elementary and preschool students are not allowed to return for the moment. (Photo by Mohamed Nasr/Xinhua)
