This unit, one of six which comprise the Fair Play program, examines male and female characteristics and behaviors in relation to genetics and environment. The Fair Play program is a series of student and teacher materials the purpose of which is to help students expand their female or male self-concepts, increase their decision-making skills, and improve their academic achievement by changing their stereotypic attitudes toward particular content areas. This student guide contains 17 lessons organized into four parts: (1) female and male attitudes toward science; (2) role of chromosomes and genes in human development; (3) relationship between humans and their environment; and (4) environmental decisions related to technology, lifestyle, and society. The lessons include learning activities for individuals and groups, discussion items, and evaluation exercises. (DC)