Purpose: There is an important need for interprofessional practice (IPP) between speech-language pathologists (SLPs) and classroom teachers (CTs) in mainstream schools to support student outcomes. This mixed methods systematic review aimed to synthesize existing literature to describe the experiences of IPP between SLPs and CTs in mainstream schools. Method: A systematic review protocol was utilized to conduct a comprehensive search of six databases (PubMed Central, EMBASE, Cochrane Library, CINAHL EBSCO, ERIC, and ProQuest Dissertations & Theses Global) using key words related to the research question. A total of 1,876 unique studies were retrieved. Of these, 18 studies were identified as relevant to the research question, as they described the experiences of IPP between SLPs and CTs. Thematic analysis was used to analyze the quantitative and qualitative studies. Results: Six main themes describing IPP experiences were identified: (1) what are you bringing to the collaboration table? (2) putting the value in collaboration, (3) sharing is collaborating, (4) the nature of collaboration varies, (5) the educational context matters, and (6) influences to collaboration beyond professional control. Conclusions: IPP between SLPs and CTs is complex, with various facilitators and barriers to IPP emerging within the education context. Competencies for SLPs and CTs related to having a shared understanding, adequate communication, and building relationships with each other help support IPP in schools. The utilization of a relationship-centered care approach between SLPs and CTs is also important to foster and support student outcomes.