Free teaching materials suitable for elementary school science available from 168 agencies and companies are listed. Materials include booklets, teacher's source books and guides, charts and posters, and concrete materials such as mineral samples. Suggestions and materials for student activities range from experiments to song sheets. Topics include conservation and use of natural resources, forestry, wildlife, animal care, health education, space science, industrial processes and commercial products, and information on science careers. Annotations indicate the content and quality of the materials. Each entry is coded for appropriate level (upper or lower elementary) and for suitability for teacher reference or student use. (EB)