This study was undertaken to ascertain the degree of stability of significant gains made in intellectual functioning by a group of children who attended Head Start programs and two groups of children who did not attend preschool programs. Data collected and analyzed at postkindergarten showed nonsignificant differences between performance levels of the experimental group and the control groups in intellectual functioning, the phonemes test and the letter names test. The experimental group performed significantly below one control group on the learning rate test. Data collected and analyzed at post-first grade showed nonsignificant differences between performance levels of the experimental group and the control group in intellectual functioning, on work study skills and arithmetic. The experimental group performed significantly below the control groups on paragraph meaning and vocabulary. (Author)