ABSTRACT
Naturally there is even more documentation and empirical evidence for the effects of social class and associated environmental conditions on intelligence and achievement in the USA. If anything the correlations are higher because of the greater heterogeneity of the population. Historically the lowest socioeconomic classes have been largely composed of negroes or of recent immigrants — Italians, Irish, S.E. Europeans and now Puerto Ricans and Cubans, and they have produced the greatest problems of school adjustment and achievement. A similar situation is emerging in Britain today with immigrant West Indians, Indians, Pakistanis and Cypriots. But all the researches cited in Chapter X were based on almost wholly white populations, whereas to a much greater extent in the USA socioeconomic class is intermixed with ethnic group * and linguistic, or with racial, differences. In the larger cities, the poorest housing areas are peopled more and more by negroes, and by still incompletely acculturated immigrants, while the whites move out to better areas with higher standards of schooling. Again over the country as a whole there is greater heterogeneity, with pockets of extreme economic and educational backwardness, so that rural vs. suburban (rather than urban) differences in ability are often much greater than any recorded in Britain. Likewise differences in quality between schools in the best and worst areas are exaggerated.
