The purpose of the study was to experimentally test the theory that programed instruction can satisfactorily teach psychomotor tasks which primarily require the learning of cognitive knowledge in order to properly utilize motor skills already possessed. A programed unit on regrinding drills was selected, and a dexterity test and self-instructional materials were developed. A cluster sample of 146 ninth, 10th, and 11th grade vocational agriculture students, selected from 21 New York schools, was tested on reading ability and dexterity, assigned to arbitrary levels based on scores, paired according to skill levels, and randomly assigned to experimental and control treatment groups. The control group had only programed instruction and the experimental group had both programed instruction and self-instructional practice. Both groups were given a performance test, and the control group was given a performance retest. Analysis of covariance procedures were used to analyze the data. The data failed to support the theory. Self-instructional practice used to supplement the programed materials did not produce significant benefit over use of the program alone. Findings clearly indicated a significant relationship between student dexterity and ability to learn psychomotor skills effectively through use of programed materials. A bibliography is included. This Ph.D. thesis was submitted to Cornell University. (JM)