When can kids safely take off their masks in school? About three-fourths of the nation's largest districts required masks at the start of the school year. Recently the calls by some parents to unmask children have grown louder, especially now that there is a COVID-19 vaccine available with emergency authorization for children as young as 5 years old.

The country is still in a pandemic that's killing more than 1,000 Americans every day. And a body of evidence shows masking, in combination with other safety measures, effectively cuts COVID-19 transmission in K-12 schools. Masks are cheaper than renovating school buildings to improve ventilation or create outdoor learning spaces, and they're (still) easier to get ahold of than COVID tests, which can also be used to prevent transmission.