Reform initiatives for improving undergraduate science, technology, engineering, and mathematics (STEM) education have identified graduate students as important stakeholders in these efforts. Graduate students often serve as graduate teaching assistants (GTAs) at some point in their graduate education and are positioned as future STEM faculty and mentors for the next generation of scientists. Therefore, institutions across the nation have recognized the importance of GTA professional development (PD) and have implemented some form of teaching PD for their graduate students. Yet, scholars suggest that current approaches to GTA PD are too focused on content and logistics and may not be providing graduate students with quality and effective PD (Schussler et al., 2015). Gardner and Jones (2011) suggest four necessary components of a quality and effective GTA program: (a) intensive, ongoing, and connected to practice; (b) focused on student learning and addresses the teaching of specific curriculum content; (c) aligned with college or university improvement priorities and goals; and (d) building strong working relationships among colleagues. In this dissertation, I suggest Lesson Study (LS) as a quality and effective PD model for GTAs and higher education instructional teams. The current study investigated the implementation of a modified LS model with two instructional teams, comprised of one course instructor, one lab coordinator and six GTAs, who taught virtual introductory chemistry labs during a summer academic term. The data I analyzed in this dissertation includes transcripts from weekly instructional team meetings, post-participation interviews with participating GTAs, and researcher-generated field notes. I employed the Five Teaching Perspectives framework (Collins & Pratt, 2011) to characterize how LS mediates instructional team discourse around teaching. Findings suggest that LS promotes the apprenticeship and developmental perspectives. I also applied sociocultural theories of learning to understand how LS mediates the roles and responsibilities of GTAs within the larger departmental context. Findings suggest that LS gives instructional teams the opportunity to confront implicit departmental norms about teaching and establish new norms. Lastly, I used design-based research to produce four design features that enhance the LS process for GTAs and instructors in higher education.