elaborated and restricted speech codes A distinction formulated by Basil Bernstein, a leading figure in the sociology of education, which contrasts the so-called formal language of middle-class children with the public language of the working class (see his Class, Codes and Control, 1971–7)
. These linguistic codes were said to be correlated with class differences in family organization, power, and control. The elaborated code of the middle class is institutionalized in schools. This results in ‘culturally induced backwardness’ among working-class children. Bernstein's research projects at the London University Institute of Education appeared to confirm these ideas, but the results of replication by others in Britain and the United States have been more ambivalent. His use of terms like class and code has also been criticized, albeit sometimes unfairly, for their ambiguity and implicit disdain for working-class life.

Bernstein was one of the first sociologists to place the problem of knowledge at the centre of the study of educational process. This was taken up by the ‘new’ sociology of education of the early 1970s. His work is usually discussed in two phases, though it is underlain throughout by concerns which reflect the influence of Émile Durkheim, in particular social symbols, classification, and cognitive processes. The earlier studies of social class and linguistic codes did much to initiate a sociology of language. His later works deal with the classification and framing of educational knowledge. Classification refers to the variability of boundaries in curriculum content (for example between school subjects); framing addresses the relative openness of teacher-pupil relationships. These concerns led Bernstein to a critique of progressive classroom pedagogies because of their invisible link to middle-class rather than working-class child-rearing styles.