FILE - In this Feb. 2, 2021, file photo, students wear masks as they work in a fourth-grade classroom, at Elk Ridge Elementary School in Buckley, Wash. Amid mounting tensions about school reopening, the Centers for Disease Control and Prevention planned to release long-awaited guidance Friday, Feb. 12, 2021, on what measures are needed to get children back into the classroom during the pandemic. (AP Photo/Ted S. Warren, File)