This research focuses on professional learning of experienced Mid-Career teachers, conducting long-term study leave for their professional growth. The need for professional learning is being emphasized internationally: “… the world of education and training is changing, and so is the occupation of teachers and trainers, with increasing demands, responsibilities and expectations”(Official Journal of the European Union, 2020) We are facing various global challenges which young generations must confront in the future and find solutions for them. As a result, the content of school education is expanding beyond typical capacities of teachers.

    The Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT, 2012 p.2) emphasizes: “To respond to the rapidly changing demands of society …, teachers must possess a spirit of inquiry and remain continuous learners.” and “It is necessary to construct institutional mechanisms that enable teachers to maintain a commitment to ongoing learning across the span of their professional lives.” Also, The Act on Special Measures concerning Education Personnel (Japan, Act No.1 of 1949) clearly articulates the necessity for teachers to engage in continuous professional development in Japan.

   However, this begets a fundamental question: Is more learning what is actually needed for teachers now? If so, how can teachers, especially experienced-teachers, learn more positively? Demonstrable willingness and intrinsic motivation to engage in learning is crucial for the success of professional development programs (cf. Liu, Li & Zou, 2016). My personal experience as a teacher in Japan supports this too. Creagh and colleagues(2023) have shown that teachers’ work has become increasingly demanding due to both heavy workload and intensified work practices. Something may need to be done before they engage in professional learning. They are often compelled—through policy directives—to participate in mandated professional development and often treated like ‘dry sponges’ and expected to quickly absorb new knowledge and skills. However, this mindset is questionable when promoting or planning professional learning programs. UNESCO(2024) reports that excessive workload and expanding role expectations limit teachers’ access to professional learning opportunities. We should regard them as ‘sponges filled with water’. Teachers, especially mid-career teachers, have much experience, skills and knowledge. Clearly, the first thing they must do is to squeeze water out of the sponge.

　A teacher’s length of service is not necessarily proportional to their level of pedagogical skill or knowledge. It is worth considering the characteristics of teachers' work from the perspective of overlearning. While overlearning enhances retention, accuracy and automaticity by continued practice, it may hinder flexible transfer or deeper conceptual understanding.(Schön,1983) When applied to the teaching profession, these insights suggest that years of accumulated classroom routines may solidify into automatic practices that teachers rarely question, even when these routines no longer correspond to the diverse, complex demands of contemporary schooling. (Berliner, 2001) In this sense, professional experience can paradoxically become a barrier to growth. Huberman (1993) demonstrates that experienced teachers frequently reach a crossroads in their careers, where accumulated experience may lead either to professional renewal or to increased caution, stagnation, and distancing from further growth.

    This research aims to examine long-term study leave as a form of professional development. Taking a long-term professional learning course and having an extended period allows them to thoroughly reflect on their teaching experience (Darling-Hammond et al. 2017). Additionally, by conducting research that links this experiential knowledge with theory and critically examines it, teachers can discover both their past selves and who they should become. Furthermore, this research seeks to generate insights into the development of more effective professional learning frameworks for teachers by conducting an analysis with the current in-service teacher learning systems in Japan.

This research adopts (1)a comparative research design combining international and Japanese secondary data analysis, (2)policy document analysis, and (3)semi-structured interviews with Japanese teachers. By triangulating these sources, the research aims to illuminate structural constraints on teachers’ professional learning and to examine the potential of long-term study leave as a form of mid-career professional development. First, international survey data from the OECD’s Teaching and Learning International Survey (TALIS 2024) are analyzed to establish a comparative context for teachers’ engagement in professional learning barriers, with particular attention to time constraints, workload, and incentive structures. These data situate Japan within broader international trends and provide an empirical baseline for understanding systemic pressures on teachers’ learning across education systems. Second, I conduct a document-based analysis of professional development policies and legal frameworks governing in-service teacher education in Japan. Official policy documents issued by MEXT, statical reports on teacher training participation, and related legislative texts are examined. This analysis focuses of the alignment - and misalignment – between policy intentions and actual implementation, especially regarding long-term training opportunities such as study leave or graduate-level enrollment. To highlight institutional differences, the analysis distinguishes between public and private school systems, noting differences in legal obligations, participation requirements, and incentive structures for professional development. Third, I analyze qualitative data collected/will be collected through semi-structured interviews in the summer of 2025 with six in-service teachers who temporarily left their teaching positions to enroll in a two-year professional graduate school of education. The participants are employed at two different private secondary schools. Unlike public school teachers in Japan, they are not entitled to participate in nationally funded long-term study leave programs. Instead, their opportunities for professional learning depend largely on the policies and financial decisions of the school corporations that operate private schools. The study therefore examines cases in which private school corporations invest in teachers’ professional development by supporting long-term study leave. By focusing on teachers who pursued advanced study without access to national training schemes, the research highlights alternative model of professional learning driven by institutional commitment rather than government mandate.

The survey on ‘Continuous Professional Learning’ (TALIS 2024) shows that higher percentage of teachers in Japan find it difficult to participate in professional learning because of lack of time, compared to that of other countries. On top of that, more than half of them wish to continue learning, but their busyness prevents them from doing so. According to Eurydice report. (2021), “Teachers may take long study leave in approximately one third of the education systems analysed. ” In contrast, Japan lags behind many European countries in terms of opportunities of long-term study leave, only a thousand public school teachers from kindergartens through upper secondary schools conducted a long-term study leave in 2023. (MEXT, 2023) Individuals with prior training experience account for only 0.1% of the total. Findings from the interviews with teachers suggest that the long-term study leave not only enabled them to critically reflect on their careers but also contributed to a transformation in their professional orientation and sense of engagement with their work following their return to the workplace. One of them commented,” Gaining a new perspective on teaching has been highly significant”. Other participants also perceived a range of effects and benefits from participating in the program. These can be broadly categorized into the following three types: (1) Recognizing their immersion in experience (2) Changes in practice or behavior (3) The Discovery of a renewed sense of professional self Their post-program reflections can be analyzed as indicating the development of a highly positive and more autonomous sense of themselves as teachers. Finally, questions concerning how the outcomes of long-term study leave should be evaluated, how national-level systems might be expanded, and what implications these findings may have for the further development in financially constrained private school contexts remain areas for future consideration.

Berliner, D. C. (2001). Learning about and learning from expert teachers. International Journal of Educational Research, 35(5), 463–482. Donald A. Schon（1983）The Reflective Practitioner How Professionals Think in Action European Commission/EACEA/Eurydice, 2021. Teachers in Europe: Careers, Development and Well-being. Eurydice report. Luxembourg: Publications Office of the European Union. Huberman, A. M. (1993). The Lives of Teachers. London: Cassell / New York: Teachers College Press. Linda Darling-Hammond, Maria E. Hyler, and Madelyn Gardner, with assistance from Danny Espinoza(2017) Effective Teacher Professional Development, Learning Policy Institute | Research Brief Liu, Ws., Li, XW. & Zou, Ym. The Formation of Teachers’ Intrinsic Motivation in Professional Development. Integr. psych. behav. 53, 418–430 (2019). https://doi.org/10.1007/s12124-018-9465-3 OECD. (2024). Results from TALIS 2024: The Teaching and Learning International Survey. Paris: OECD Publishing, Chapter 3, pp. 120–17 Official Journal of the European Union Council conclusions on European teachers and trainers for the future (2020/C 193/04) Sue Creagh, Anna Hogan, Greg Thompson, Nicole Mockler and Meghan Stacey(2025) Educational Review 2025, Vol.77, No.2, 661–680 Workload, work intensification and time poverty for teachers and school leaders The Ministry of Education, Culture, Sports, Science and Technology (MEXT, 2012) Report on Comprehensive Measures for the Integrated Development of Teachers’ Competencies Throughout Their Professional Careers The Ministry of Education, Culture, Sports, Science and Technology (MEXT, 2023) Survey Results on the Implementation Status of Graduate School–Based In-Service Training Programs https://www.mext.go.jp/content/20250307-mxt_kyoikjujinzai01_-100002375_3.pdf UNESCO(2024) Global Report on Teachers : addressing teacher shortages and transforming the profession, UNESCO International Task Force on Teachers for Education 2030