This document describes a home-based enrichment program for preschool children in Israel. The Home Instruction Program for Preschool Youngsters (HIPPY) provides weekly packets of educational activities to mothers and their educationally disadvantaged children of 4 to 6 years of age. Families selected for the program are of Afro-Asian origin, have less than 10 years of education and have low incomes. The mother who joins HIPPY meets weekly, either individually or in a group, with a paraprofessional aide, who instructs her in how to administer the materials to her child. Aides are selected and supervised by local coordinators who are guided by a regional coordinator who in turn is selected by the national administrator of HIPPY. The effects of the program have been studied since 1969. Generally, the studies indicate that HIPPY improves disadvantaged children's school performance. Further, the data from the HIPPY program show that the impact of the program can be increased through additional home-based activities with the mother. Participating mothers appear to change their behavior and attitudes, improve in self concept and participate increasingly in away=from-home activities. It is suggested that the basis for the program's success is that parents can see positive changes in their children and can anticipate their future success in school. (Author/RH)