This preliminary directory represents the offerings of 45 software suppliers and information about instructional software currently available for three microcomputers widely used in schools. It is geared towards a wide variety of users including school planners contemplating microcomputer acquisition, teachers planning courses and curricula, media center personnel, schools of education, and home computer users. The directory is organized as follows: (1) software descriptions in sequence by school department, subject, and lowest grade level; (2) summary listings of software for individual hardware systems, in the same sequence as the first section; (3) an alphabetical listing of software suppliers and their addresses; and (4) a glossary of terms used. Software descriptions include the program name, department, subject, grade level range, program type, and functional description, as well as intended hardware system(s), source, and retail price. The summary listing contains only the program name, grade level range, functional description, and an identification number which refers back to the more complete entry in the first section. (Author/MER)