On a recent weekday morning, librarian Annabelle Blackman stood in front of a room full of young children at the Cesar Chavez Public Library in Oakland, Calif., singing a children’s rhyme and swaying ...

The library is supposed to be, by its very essence, a quiet place. A place of study and comprehension, and of deep, immersive reading. The Athenaeum Music & Arts Library in La Jolla is such a place.

Most of the 20 or so tables in one reading room were occupied by young people buried in their books, with some desks already ...