Across many education systems, substitute teachers have become an essential yet structurally marginal workforce. In Taiwan, demographic decline and flexible staffing policies have intensified schools’ reliance on substitute teachers, including those without formal teaching certification. Despite their increasing presence, substitute teachers often experience unstable employment conditions, ambiguous authority, and limited institutional support, raising critical questions about how teacher professionalism is constructed under precarity.

Existing studies have examined substitute teachers’ job satisfaction and working conditions (Glaveli et al., 2023; Schkolenko, 2018), as well as early-career substitute teachers’ adaptation within formal teacher education systems (Chang, 2010; Kuo, 2023). However, less attention has been paid to how substitute teachers themselves interpret institutional constraints and actively negotiate professional action in everyday school life. Responding to the ECER 2026 theme Knowing and Acting: The Changing Conditions and Potentials of Education Research, this study explores how professional knowledge and action emerge within institutional gaps.

This paper addresses the following research questions:
(1) How do substitute teachers interpret their professional roles and responsibilities within different institutional contexts?
(2) How do administrative arrangements, assessment practices, and inter-teacher relations shape substitute teachers’ meaning-making processes?
(3) How does substitute teachers’ structural mobility influence their professional agency and decision-making?

The study adopts an interpretive and meaning-oriented theoretical framework, viewing teacher professionalism as a situated and negotiated process rather than a fixed outcome of certification. Drawing on perspectives of teacher identity, institutional precarity, and professional agency, the paper conceptualizes substitute teachers as actors who continuously interpret, adapt to, and sometimes resist institutional arrangements.

By focusing on substitute teachers’ lived experiences and reflexive interpretations, this study contributes to international discussions on teacher professionalism, educational inequality, and governance. It foregrounds how professional knowing and acting are shaped within incomplete institutional structures and highlights the transformative potential of research that takes marginal educational actors seriously.

This study employs a qualitative research design combining semi-structured interviews, participant observation, and reflexive field notes. The primary data consist of in-depth interviews with three substitute teachers working at the same lower secondary school in Taiwan: an English teacher, a mathematics teacher, and a counseling teacher. The participants differ in subject area, career background, certification status, and life circumstances, allowing for comparative analysis across professional trajectories. In addition to the initial interviews, the researcher conducted ongoing participant observation throughout the academic year, gaining further insights into participants’ institutional positioning, workload arrangements, and career considerations. Supplementary observations also include informal conversations with substitute teachers from other schools, enabling cross-county and cross-school comparisons regarding administrative practices and role expectations. Data collection focused on key areas such as teaching assignments, assessment design, administrative coordination, inter-teacher conflicts, student management, and career decision-making. Particular attention was paid to moments of institutional breakdown, role ambiguity, and professional negotiation, as these situations revealed how substitute teachers make sense of their positions. Data analysis followed a thematic and iterative approach. Interview transcripts and field notes were coded to identify patterns related to meaning-making, institutional constraints, professional agency, and mobility. Reflexive analysis was employed to acknowledge the researcher’s positionality while ensuring that analytical emphasis remained on participants’ interpretations and actions rather than autobiographical narrative. Ethical considerations included informed consent, anonymization of participants, and careful handling of sensitive institutional information.

The findings suggest that substitute teachers’ professionalism is constructed through ongoing negotiation within institutional gaps rather than derived solely from formal status. Participants frequently assumed substantial teaching responsibilities while lacking corresponding decision-making authority or administrative protection, leading to the personalization of professional risk. Differences across cases reveal how institutional conditions intersect with teachers’ backgrounds. The mathematics teacher’s cross-disciplinary training and geographical mobility illustrate how career planning involves balancing institutional advancement with personal and familial considerations. The English teacher’s experiences highlight how assessment disputes and workload allocation expose substitute teachers to conflict without adequate procedural support. The counseling teacher’s relative economic security enables alternative relational practices with students that fall outside standardized professional training yet prove effective in practice. Across cases, high mobility—often framed as a structural weakness—emerges as a potential source of agency. The option to leave unsustainable environments provides substitute teachers with psychological and practical leverage to set boundaries, voice concerns, and make professional choices. These findings challenge deficit-oriented views of substitute teachers and suggest that educational systems should reconsider how professionalism, support, and responsibility are distributed. The study contributes to the ECER 2026 theme by demonstrating how educational research can illuminate the conditions under which marginalized actors transform precarity into meaningful professional action.

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