Appropriateness and reinforcement value of teacher language in middle and low socioeconomic school settings were investigated, using one hundred and four 5-minute tape recorded language samples from 15 teachers in seven schools. In the first analysis, a correlation of .64 (p<.01) between the words in this language corpus and those in the Thorndike-Lorge and Rinsland listings was found, indicating a high degree of overlap in the oral and written language to which these children are expected to respond. With reference to verbal reinforcement, analysis of the nature of the communications conveyed by the teachers' language revealed a number of interesting differences across ethnic and SES groups. White teachers of both high SES black children and low SES white children used a great deal more verbal reinforcement than white teachers of high SES white children or black teachers of low SES black children. However, the statements of the white teachers in the first group were primarily punitive, whereas the reinforcement messages of the black teachers of low SES black children were overwhelmingly positive, warm, and supportive. Only white teachers were observed in high SES schools, with neither white teachers of low SES black children nor black teachers of high SES black children or low SES white children. Therefore broad generalizations should not be drawn from this incomplete sample. (Author)