The flipped classroom is a teaching innovation in which instructional content is delivered out of the classroom, often via videos, and the class period is used for application of the course material. While the popularity of the flipped classroom is growing exponentially, its benefits have not been extensively studied. In this study we compared three semesters of an undergraduate Genetics course that was non-flipped, but included a significant amount of active learning, to three semesters of a flipped course with the same content. Student exam performance was not statistically different between the active non-flipped and the flipped courses, suggesting that the benefits of the flipped environment may be similar to those achieved via active learning. We also examined student attitudes toward the flipped classroom, and found 56% of students were satisfied, 39% were dissatisfied, and 5% were neutral toward the flipped classroom. Our survey revealed that the clearest defining characteristic of dissatisfied students was not a dislike of classroom active learning activities. Rather, dissatisfied students disproportionately disliked, and had difficulty learning the course material, from videos.