This article fills in the knowledge gap in the student-centered practices of generalist music and art teachers to prepare 21st century learners. The study shows that generalists, after completing a specialist professional development program, struggle the most in connecting subject matter knowledge to pedagogical knowledge, specifically student-centered classroom pedagogy. The study confirms previous literature on the shortfall of professional development training in adequately preparing generalists in the arts and supports the recommendations that advisory teachers and continuous professional development support are needed to increase the self-efficacy of generalists.