EditorialPrecious Coleman helps her son Jordyn, 11, with a class assignment at their home in Clarksdale, Miss., on Feb. 3, 2021. (Tamir Kalifa/The New York Times)
EditorialSmart thermometers made by Kinsa. a company that has tracked the flu in the U.S. by aggregating data on fevers, in New York, Oct. 19, 2018. (Tony Cenicola/The New York Times)