To determine whether student achievement could be improved by matching cognitive style to instructional mode, a study was undertaken with 184 high school sophomores and juniors. Students were tested for reading and listening ability and preference and assigned to instruction based on reading and audio presentations. Ability was also tested. Students were divided into eight groups and achievement tests administered after instruction. Tests indicated that on the basis of the instruments used, a valid and predictive diagnosis of cognitive style could not be developed; that reading or listening preference did not measurably affect achievement, and that the reading mode was more effective than the listening mode. Copies of the survey instruments, script for the audio presentation, and the posttest are included. (SK)