Two alternate subject-matter units were presented by printed text, printed text with supplementary programmed items, printed text with supplementary laboratory manipulations and observations, taped audio program with supplementary programmed items, or taped audio-tutorial program with supplementary laboratory manipulations and observations during the development of a "minicourse" on Physical Phenomena of Cells. The content mastery scores attained were analyzed in a 2 x 5 x 2 analysis of variance, with student ability level as the third variable. Since there was no significant interaction between ability, instructional method, and subject-matter unit, and no significant main effect of instructional method, the final version of the minicourse was designed to contain alternative instructional procedures to allow for individual student preferences. (Author/AL)