The main purpose of this study was the development and evaluation of a unit of study for underachieving sophomores enrolled in basic-vocational mathematics. Students in this category were identified through the guidance office and by considering scores on the California Achievement Test and the Differential Aptitude Test. These students were randomly assigned to treatment and control conditions. The instructional treatment was determined in part by interests expressed by students in the experimental group. Materials used were selected from currently published mathematics books as well as publications in the field of industrial and technical education. Pretest results, student suggestions, and the recommendations of experts in working with underachievers were considered in the selection of materials. Treatment lasted for twelve weeks. A t-test was used and showed that achievement by the experimental group was significantly greater than that of the control group. (Author/SD)