This action research study provides insight into the learning of university music education students who participated in a popular musicianship experience. The participants were thirty-four music education students (i.e. pre-service music educators) at an American university enrolled in a student-directed Popular Musicianship course. Although given access to "rock band" instruments and sound equipment during the semester-long experience, they did not receive any direct instruction from the faculty instructor of record. After organizing into bands, the participants were challenged to prepare for performance two or three songs, including one cover and one original song. They also indicated the confidence they had in their ability to lead their future students in popular music making. This measure of self-efficacy was collected at the beginning, middle, and end of the experience. Also, participant written descriptions of their experiences was analyzed qualitatively. The findings of the study indicated that participants believed their overall musicianship benefited from the experience due to the challenging nature of vernacular music making, which was also enjoyable and rewarding. The experience also appeared to impact their teaching philosophies for the future. Finally, their self-efficacy increased significantly across the experience.