Given the relatively high intercorrelations observed between mathematics achievement, reading achievement, and cognitive ability, it has recently been claimed that student assessment studies (e.g., TIMSS, PISA) and intelligence tests measure a single cognitive ability that is practically identical to general intelligence. The present article uses…

Existing evidence on the Milwaukee Project, an early intervention effort with preschool disadvantaged children, suggests a decline of the experimental children to the level of the untreated controls in those measures, such as school reading, not under the control of the project. (DB)