FILE — Lear Preston, 4, who attends Scott Joplin Elementary School, participates in her virtual classes as her mother, Brittany Preston, background, assists at their residence in Chicago's South Side, Feb. 10, 2021. Schools across America are racing to make up for lost classroom time, budgeting billions of dollars for tutoring, summer camps and longer school days. But figuring out which students need help has become its own challenge after the pandemic left holes in some students' learning records. (AP Photo/Shafkat Anowar, File)