This research project evaluated and compared three educational programs of high, medium, and low structure in family day care settings for a period of 10 months, to determine their impact on cognitive and social development in 60 children aged 2 1/2 to 4 years. The high-structure program followed the Bereiter-Engelmann approach, the medium-structure program was an adaptation of Levenstein's Verbal Interaction Program, and the low=structure situation involved friendly visitation with a child by an adult with no consistent philosophy or pedagogical program. A total of 52 children was assigned to experimental groups which differed on two main dimensions: the degree of structure and the delivery system. The two delivery systems consisted of paraprofessional teachers wither working alone with the children or cooperating with the day care mother. In addition, eight children were assigned to a family day care control condition. Results of pre- and posttesting with three cognitive measures indicated that children in each of the intervention groups showed improvements above those of the control group, but that there were no differences between intervention groups. No distinct pattern of effects was found on the sociobehavioral ratings made by teachers for any of the experimental groups. (GO)