Research has shown that differences among ordinary people in intelligence and personality depend equally on individual genetic variability and on differences in the environments that siblings experience within the same family, not differences in the neighborhood, school, and community environments. As of yet, there are no adequate theories to…

Until the 1970s, there were few signs of change in the historic difference of one standard deviation between average ability or achievement test scores of black and white students. From 1970 to the mid-to-late 1980s, there was a substantial convergence of the average achievement test scores of blacks and whites. From the mid-to-late 1980s to 1992,…

This paper explores the reasons for the rapid adoption of intelligence tests by the public schools, and the historical relationship between testing and ability grouping or tracking. Case studies are presented of three California communities--Oakland, San Jose, and Palo Alto--between 1910 and 1925. These communities have been selected because they…