Future doctors in Birmingham get a leg up by studying a bicycling skeleton. Aspiring engineers in Oak Ridge, Tenn., explore a model coal mine. In New York City, make-believe media moguls produce their own sitcoms in a TV studio. A decade ago, it would have been hard to find such innovative exhibits in children's museums. For the most part, those museums were pint-size versions of adult institutions, where kids were expected to keep their mouths shut and their hands in their pockets.
These days, however, children's museums have been dusted off, jazzed up and wired for action. Young visitors are increasingly...