This book aims: (1) to describe and evaluate psychological research on poor children's intellect; to this end, the following questions are dealt with: What is the nature of poor children's mental abilities? How do these abilities develop? (2) to analyze the psychological assumptions underlying several attempts to reform education; and, (3) to describe psychology's potential contribution. To achieve these aims, the author selectively reviews and analyzes several crucial studies under the following broad categories: IQ; language; intellectual abilities; development; and, intellect and the schools. In addition, a number of case studies and journalistic reports have also been included. (Author/SB)