A project was devised to extend the applicability of a previously developed computer-assisted instruction (CAI) course in instrumental musicianship (see ED 035 314), and to assess its effects through the development and implementation of criterion referenced measures. Twenty-five intermediate level students of treble clef wind instruments participated as subjects in the evaluation phase of the project: all students were given a listening pretest involving aural and aural-visual discrimination and a performance pretest; attended a CAI lab twice weekly which included online listening and coordinated offline practice; and completed posttests which were the same measures administered previously as pretests. Group gains in both listening and performance were significant and dramatic; since the students had been playing these instruments for five or more years, it is presumed that the results can be attributed to the experimental treatment even without comparison with a control group. (SH)