FILE - In this Nov. 19, 2020 file photo, teacher Susannah Remillard, middle, speaks to one of her sixth-grade students at Cape Cod Lighthouse Charter School, in East Harwich, Mass. U.S. guidelines that say students should be kept 6 feet apart in schools are receiving new scrutiny from federal health experts, state governments and education officials working to return as many children as possible to the classroom. (AP Photo/Elise Amendola, File)