Nowhere has the logic of IQ tests had more influence than in the field of educational psychology and in the American school system. Access to educational opportunity has been a boon in many respects, but it has also naturalized socioeconomic inequality, in part because decisions about access exploit the comparative logic at the heart of IQ tests. In its earliest forms in the years around 1905, the French psychologist Alfred Binet used a series of tests to define what a child should be able to do at a particular age. The first test consisted of a series of 30 short tasks—related to expectations for comprehension, reasoning, and memory—that were sequenced according to their difficulty. A child proceeded through the exam until she could no longer complete the tasks. The age associated with the last task she could perform was her assigned mental age. To be sure, IQ scores are now calculated in a more complex way, but their meaning still emerges through a logic of comparison. Plotted on a bell curve, “the intellectually disabled” and “the gifted” are, through the logic of a graph, shown to be objectively different from the great swathe of “normal” people in between.
But over time, what constitutes a “gifted” as opposed to a “normal” or “intellectually disabled” student has fluctuated, revealing the historical and social contingency of such categories. For example, in 1959, former president of Harvard University James Bryant Conant proposed moving the cutoff for labeling a student as gifted to an IQ score of 130, 10 points lower than what psychologist Lewis Terman had established 30 years earlier. Suddenly—due to the act of moving a line on a graph—there were a great many more “gifted” students. This shift dramatizes the arbitrary nature of matching score to label. Why not 125 or 135 instead? The stakes are even higher on the other side of the bell curve: people with an IQ score of 72, for example, might be denied the support and services that accompany a diagnosis of “intellectually disabled” if the cutoff is 70. Or, alternatively, they might escape forced sterilization if they happened to live in Oregon before 1981. (Oregon was the last state to uphold the practice.) The story of eugenics, IQ tests, and education is, then, about who gets the best opportunities and who gets discriminated against, all in the name of commensuration.