The purpose of this study was to examine the intergenerational interactions between preservice music teachers and senior adult musicians engaged in music teaching and learning in a New Horizons ensemble within one university's music teacher preparation program. This intrinsic qualitative case study included written reflections and observational data of 16 current undergraduate music education students and verbatim interview transcripts of 5 current and former students serving as teaching assistants who taught and conducted their university's New Horizons ensemble. Findings distilled from the data included (a) how younger-aged preservice music teachers responded to generational differences while learning how to interact with senior adult musicians; (b) the pedagogical content knowledge (PCK) learned and developed by participants as a result of teaching in a New Horizons ensemble; and (c) the connections made by participants teaching senior adults to their future careers as professional music educators. Future discussion and directions from this study highlight emerging connections of research between adult and community music settings and music teacher education. Implications include (a) how to create best practices so that the missions and objectives of both music teacher education programs and cooperating community adult ensembles support and enhance each other; (b) fostering outcomes that prepare music education majors for experiences in adult music education; and (c) reimagining New Horizons and music teacher education partnerships that result in more national, racial, cultural, and musical diversity and inclusion. [This study was presented at the Desert Skies Symposium on Research in Music Education on 22 February 2019 in Tempe, AZ, United States.]