The Early Childhood Education Project (ECEP) is an experiment in the effects of educational intervention of two-year-old first-born children from impoverished black families. Twenty ECEP children were compared to a control group on the basis of a battery of pre- and post-tests after six months of intervention training. Teachers attempted to develop social-emotional adjustment and cognitive behavior. Training occurred in both group and tutorial sessions. Narrative observations, rating scales and observation of test-related behaviors were measures of social-emotional development and a battery of tests measured cognitive skill. Preliminary findings indicate that the intervention program was effective in the development of cognitive skills, especially in language, pantomime, seriation and train building. Only sex differences are compared for social-emotional development. Boys were more cooperative, defended their possessions and were more aggressive to people and objects than girls. Girls were more compliant to demands and initiated more interactions with teachers. (DG)