This chapter takes up the pressure under which preschool enrichment programs like Project Head Start—promoted by President Johnson as signature components of his War on Poverty—found themselves, in needing to demonstrate that they were worthy of investment, rather soon after they had been launched. A most significant turning point came in 1966 with the Equality of Educational Opportunity report (better known as the Coleman Report). Expected to demonstrate that students in segregated schools lagged in IQ scores, the Coleman Report instead had the effect of calling into question the conviction, so essential for advocates of desegregation and early enrichment alike, that children’s brains were malleable and that changing their environments improved their IQs. At the same time, a host of seemingly unrelated psychological theories – e.g. “locus of control”, learned helplessness, the interpersonal expectancy effect (better known as the Pygmalion effect) – got swept into controversies over the potential effectiveness of compensatory education.