Designed to help students develop interest in careers in the mathematical, physical, medical, biological, social, or engineering sciences, this directory lists programs which are intended to contribute to precollege students' academic development. These science training programs serve to provide talented high school students with educational opportunities in science, engineering, and mathematics beyond those normally available in courses or laboratory work in the students' schools. The types of training offered are described and explanations are given on how to use the directory. A reference guide lists the institutions by state and identifies the type of program sponsored. Complete descriptions of each institution's programs are presented alphabetically by state. Also provided are descriptions of the programs conducted by Science Service, Inc. These consist of the Westinghouse Science Talent Search and the International Science and Engineering Fair. (ML)