To address the need to develop a scientifically literate citizenry, the socio-scientific reasoning model was created to guide curriculum development. Goals of this developmental approach include increasing: (1) students' skills in dealing with problems containing multiple interacting variables; (2) students' decision-making skills incorporating a wide social perspective; and (3) critical thinking skills in the evaluation of consequences and implications of decisions. Secondary school students (grades 7-12, from both public and private sectors) enrolled in courses in chemistry, earth science, biology, health, social sciences, and physics are currently participating in the field test and evaluation of these curriculum materials. Tests designed to evaluate knowledge, critical thinking, and moral/ethical reasoning have been administered to approximately 1,000 students. The experimental design for the field test is the non-equivalent comparison group design where experimental and control groups are pre-tested and post-tested. Mean scores of the experimental and control groups are compared using a t-test to determine if the experimental group achieved significant improvement in the cognitive and affective domains. Preliminary analysis of the data indicate that these curricula materials have the potential to affect development in both the cognitive and affective domains. (Author/BB)