To determine the effect of different amounts of parental involvement, 80 4-year-old children from lower class homes, enrolled in a compensatory preschool program (class for one-half day, four days per week for a full year) were divided into three groups. Group I received supplementary bi-weekly tutoring from teachers with no parental involvement. Group II was tutored but in the presence of their mothers who became involved. Group III was offered the same tutoring as Group II, and mothers participated in small group discussions about childrearing. The Stanford-Binet and the Peabody Picture Vocabulary Test (PPVT) were given as pretests and posttests to all children. A revised version of the Pupil Behavior Inventory was completed by teachers and two standardized questionnaires were completed by mothers to tap attitudes toward childrearing and cognitive stimulation in the home. No significant differences were found between groups in IQ gain on either the Stanford-Binet or the PPVT, although all groups gained significantly. Significant differences did emerge on factors of parental measures, but not on the teacher rating form. Desirable changes in maternal attitudes were found in the mothers who had been offered opportunity for maximum participation. (Author/AJ)