Kindergarteners squirmed and fidgeted on a colorful rug in the Ridgway Elementary School library Tuesday, sitting crosslegged and elbow-to-elbow as librarian Kara Young read them a story.

Around the corner, second graders worked on math problems in clusters of desks, and down the hall, fifth graders ate lunch, talking and laughing loudly.

There were no plastic dividers between students, no carefully-marked distances to keep students apart, and no masks in sight.

For the first time since 2019, back-...