A 3-year project examined the potential of a computer-managed instruction (CMI) system to improve the academic performance of students in small rural elementary schools. A CMI system consisting of 32 student work stations, 6 courseware packages, 2 testware packages, and a management package was installed at 3 sites in Maryland, Pennsylvania, and New Jersey. The New Jersey school at the time the project began enrolled 180 students in grades two, three, and four; the Maryland school began with 216 students in grades K-6; and the Pennsylvania school with 275 students, grades K-5. Each had significant numbers of at-risk students. Each school year, students completed the Waterford Test of Basic Skills (WTBS) for placement, then received CMI approximately 30 minutes daily throughout the year, alternating among subjects (reading, language arts, writing, mathematics, and typing). A posttest on the WTBS and an attitude survey were administered to students at the end of the school year. Regular observations and interviews assessed teacher attitudes and practices relative to CMI. Following modest gains in the first year, achievement results in the second and third years showed significant gains for all grades and sites. Student attitudes toward their experience with computers were extremely positive and consistent. Many teachers initially viewed the program as an add-on and resented the loss of instructional time. However, in the second and third years, teachers began to incorporate CMI into their instructional activities. Contains tables detailing achievement results. (SV)