One of the first school districts in the country to reopen its doors during the coronavirus pandemic did not even make it a day before being forced to grapple with the issue facing every system actively trying to get students into classrooms: What happens when someone comes to school infected?

Just hours into the first day of classes on Thursday, a call from the county health department notified Greenfield Central Junior High School in Indiana that a student who had walked the halls and sat in various classrooms had tested positive for the coronavirus.