Forty families were selected to represent the range of typical American families in size, race, and socioeconomic status. In data from 2Vi years of once-monthly, hour-long observations of unstructured parent-child interactions in the home, parenting was examined over 27 months, including the time before, during, and after all the children learned to talk. Ten parent measures suggested by the literature all showed stability in expression within families across time but large differences among the 40 families. The 10 parenting variables clustered into 3 factors relating to (a) the absolute amount of parenting per hour, (b) parents' social interaction with their children, and (c) the contentive quality of the utterances parents addressed to their children. The amount of parenting per hour and the quality of the verbal content associated with that parenting were strongly related to the social and economic status of the family and the subsequent IQ of the child.

"Incidental teaching" denotes a process whereby language skills of labelling and describing are learned in naturally occurring adult-child interactions. In the present study, 15-min daily samples of the spontaneous speech of 11 children were recorded during free play over eight months of preschool. After incidental teaching of compound sentences, increases in unprompted use of compound sentences were seen for all the children, first directed to teachers, and then to children, in accordance with who attended to the children's requests for play materials. The incidental teaching procedure also stimulated spontaneous variety in speech, and appears to have general applicability to child learning settings.

Correspondence was developed between children's non-verbal and verbal behavior such that their non-verbal behavior could be altered simply by reinforcing related verbal behavior. Two groups of six children each were given food snack at the end of the day: for reporting use of a specific preschool material during free play (procedure A); and then only for reports of use which corresponded to actual use of that material earlier that day (procedure B). Initially, procedure A alone had little or no effect on the children's use of materials. Procedure B resulted in all of the children in one group actually using a specific material, and after repeating procedures A and B with this group across a series of different materials, procedure A alone was sufficient to significantly increase use of a specific material. Correspondence between verbal and non-verbal behavior was produced such that, in this group of 4-yr-old disadvantaged Negro children, "saying" controlled "doing" 22 or more hours later. In the second group, procedure B initially did not increase the use of a specific material; rather, the children's reports decreased so as to correspond to the intermittent use of the material. It appeared from subsequent procedures with this group that maintenance of a high level of reporting was crucial to the saying-then-doing correspondence seen in the first group.

From observer records, a count was made for each child, in a group of disadvantaged children in an experimental preschool, of usage and acquisition of descriptive adjectives, with and without noun referents. Procedures were sought which would effectively modify the low rates of adjective-noun combinations in the everyday language of all the children. Time in school, intermittent teacher praise, and social and intellectual stimulation were not effective in changing the low rates of using adjectives of size and shape. Group teaching effectively increased rates of using color- and number-noun combinations in the group-teaching situation, but was ineffective in changing rates of usage in the children's "spontaneous" vocabularies. By operating directly on the children's language in the free-play situation, making access to preschool materials contingent upon use of a color-noun combination, significant increases in such usage were effected in the spontaneous vocabularies of all the children. Preschool materials apparently functioned as powerful reinforcers. Though traditional teaching procedures were effective in generating adjective-noun combinations in that restricted situation, it was only through application of environmental contingencies that color names as descriptive adjectives were effectively and durably established in all the children's spontaneous vocabularies.

This article is a secondary data analysis of the University of Kansas Language Acquisition Project, which intensively studied, on a regular basis, parent and child language from age 6 months to 30 months. The association between residential density and parent-child speech was examined. Parents in crowded homes speak in less complex, sophisticated ways with their children compared with parents in uncrowded homes, and this association is mediated by parental responsiveness. Parents in more crowded homes are less verbally responsive to their children. This in turn accounts for their simpler, less sophisticated speech to their children. This mediational pathway is evident with statistical controls for socioeconomic status. This model may help explain prior findings showing a link between residential crowding and delayed cognitive development.