In historical parks across the U.S., tiny museum-piece schoolhouses, with belfry, potbellied stove and initial-scarred benches, set city-bred youngsters to speculating about how "cute" the one-teacher, one-room school must have been. Yet for a surprising number of children, this kind of school is neither quaint nor historical: they attend one daily. Despite the big trend toward consolidation, some 10,000 one-room schools still function in rural America.
The number has been dropping steadily: from 196,037, or 70% of public grade schools, in 1918, to 13,330, about 20%, in 1960. To survive, a...