The degree of influence instructor tutoring had on the performance of Black Hawk College sociology students was studied along with the question of whether students expressed a change in the degree of preference for the mastery approach when an instructor was actively involved in the learning process. Two classes were used: one during spring 1976 that did not receive instructor tutoring, and one during spring 1977 that did. Mean scores on a midterm exam were compared. At the close of the experiment, students were asked to express their preference for the mastery method of instruction as compared with the traditional lecture-discussion approach. Results demonstrated that there was no significant difference in the mean scores achieved on the midterm exam, nor was there any significant difference in the proportion of students expressing a preference for the mastery method when instructor tutoring was used. However, the smallness of the population tended to cause the tests to not be very sensitive. Recommendations included: (1) clarification of the mastery system in the college's schedule of classes; (2) peer tutoring; (3) increasing teachers' knowledge of and involvement with mastery learning; and (4) additional research of alternative delivery systems and student characteristics as predictors of success. (Author/LBH)