This study was designed to investigate the effect of situational variables on the persistence of 6-year-old children from varying socioeconomic and educational backgrounds. Subjects were 24 male and 24 female children selected randomly from each of four groups of first grade Negro children: one group of advantaged children who had attended preschool and three groups of disadvantaged children whose preschool background varied. In the test-like situation, nine block designs were administered from the Kohs Block Design series to provide relatively insoluble tasks to measure persistence. The difficulty level of the task was described to each child who was tested individually under conditions of reward and non-reward. Expectations based on the effects of socioeconomic and preschool experience differences in background of the four subject groups were not met. Also unsubstantiated were the expectations about the situational variables of reward presence and absence or set for task difficulty. Implications of the findings and possible design changes are discussed. (WY)