Compared was the relative effectiveness of a new college level general biology course utilizing an audio-tutorial (A-T) laboratory with a traditional lecture course without a laboratory. Five biology classes (two traditional and three A-T) with 720 students at Kansas State Teachers College comprised the population. Seventy students, 35 male and 35 female, were selected from each of the two biology groups. A 2x2 factorial design was used. The factors were the two types of biology courses, and the two sexes. The data were treated by analysis of variance. Instruments used on a post-tes t basis were the Test on Understanding Science, Form W, an attitude scale, and an investigator-prepared General Biology Test. Results indicated that the audio-tutorial course was as effective as the traditional course with which it was compared. In general students in the audio-tutorial classes attained higher scores on the criterion tests than did students in the traditional classes, although none of the differences were significant. There was also a difference between the sexes in ability to show relationships between bodies of knowledge in favor of the male students . The criterion tests and the various subtests seemed to measure distinctly different understandings about science, levels of comprehension of biology, and attitude toward science. (RS)