Several scholars argue for a closer association between research and teaching in higher education, but it is unclear how research-based teaching can be actualized. Action research (AR) offers designs that position students as actors of the research processes, for example by doing research themselves or co-researching. Therefore, AR and research-based teaching can be considered mutually nested pedagogical and methodological processes. In this scoping review, we explored studies methodologically framed as AR which involve higher education students in the Humanities and Social Sciences as participants. We focused on (1) the research characteristics and (2) how the students were positioned in the identified studies. By reviewing 218 studies in line with inclusion criteria, we found three student positions: students as researchers, as learners and active contributors to research, and as source of information. We discuss implications for teachers/researchers who adopt AR and how they can develop research-based teaching involving students as researchers.