In the first few decades of the 20th century, child prodigies became national celebrities. Much like the movie stars, industrial titans and heavyweight champs of the day, their exploits were glorified and their opinions quoted in newspapers across the United States. While every generation produces its share of precocious children, no era, before or since, seems to have been so obsessed with them. The recent advent of intelligence testing, which allowed psychologists to gauge mental ability with seemingly scientific precision, is one likely reason. An early intelligence test had been demonstrated at the Chicago World’s Fair of 1893—the same exhibition that introduced Americans to such wonders as the Ferris wheel, Cracker Jacks and hula dancing. Then, in 1916, Stanford University psychologist Louis Terman published the Stanford-Binet test, which made the term intelligence quotient, or I.Q., part of the popular vocabulary.