Preschool advocates’ claims of success are based on faulty methodology
The evidence seemed overwhelming. When Rutgers professor Steven Barnett gave a congressional briefing on preschool last spring, he touted higher test scores, improved graduation rates, reduced crime, less welfare use, and other benefits large and small. More than a hundred studies over 50 years had documented the positive impact of preschool, and the more rigorous ones had found the larger effects. The benefits were shown to far outstrip the costs. High-quality preschool clearly works, according to the presentation, and now the challenge is to give as many children as possible access to its benefits.
Just by looking at the presentation slides, you would never have guessed that, only a few months earlier, the nation’s largest preschool program had been found to confer no lasting benefits on children.