This study examines the effectiveness of a comprehensive, multi-year support program for school leaders in challenging circumstances in Germany that combines multiple strategies (professional development program, coaching, school development consultancy). Specifically, it seeks to assess participants' evaluation of the quality and usefulness of multiple interventions, as well as the effects and impact of these interventions on school leadership, school development, and school quality.

Grounded in the theoretical understanding that school leadership plays a central role in school quality and development (e.g., Grissom et al., 2021; Kovačević & Hallinger, 2019; Leithwood & Louis, 2012; Rhodes & Brundrett, 2009; Sammons et al., 1995; Teddlie & Stringfield, 1993) the research builds on existing literature that emphasizes the importance of leadership professionalization and qualification programs for school improvement (e.g., Darling-Hammond et al., 2007, 2022; Grissom & Harrington, 2010; Gümüş et al., 2024; Young et al., 2009). In this sense, leadership development is closely linked to improving school quality. Especially in schools in challenging circumstances, school leadership plays a key role, while these school leaders and their schools often require additional external support (e.g., Baumert et al., 2006; Creemers et al., 2022).

To achieve its objectives, the study employs a five-year quasi-experimental longitudinal design with a mixed-methods approach. It utilizes a sample of 75 schools participating in the program and 47 comparison schools with similar contextual characteristics. In our qualitative analyses, we use school documents (e.g., inspection reports, school strategy documents, other reports), semi-structured interviews with different actors in the schools (e.g., school leaders on various levels, teachers, and educators) held twice (at the beginning and at the end of the 3-year period), and logs of the coaches and of the school consultants, each 10 times over the 3-year period. Annual surveys of school leaders and educational staff measure intervention quality and school quality indicators at three time points. Additionally, assessments of various outcome qualities, such as goal achievement, perceived benefits, motivation increase, and competence development, are conducted. Furthermore, we analyze statistical data from the government and education authorities and student achievement data. In this presentation, we refer primarily to quantitative data. The analysis includes descriptive evaluations of quality assessments in terms of processes and results of the interventions. To examine their further impact, we conducted autoregressive regression analyses, where we consider the impact of the process qualities of school consultancy on the outcome qualities of school consultancy over time. In addition, we consider the impact of school consultancy on selected school quality characteristics over time as well as the effect size Cohen's d (Cohen, 1988) for a comparison between program and comparison schools. We also conducted further specific analysis, for instance a longitudinal latent multi-level mediation model on the direct and indirect effects of school leadership on inclusion at the school site.

Key findings indicate that participants highly rated the quality and usefulness of interventions throughout the program. Regression analyses revealed positive correlations between perceived outcome qualities of interventions and improvements in various dimensions of school quality. For example: The school members’ positive perception of the benefits (β = .26**) and goal achievement (β = .28**) as well as their perception of an increase in competence development (β = .25**), behavioral (β = .27**) and organizational (β = .15*) change through the school’s work with a school development consultant is associated with an improved coordination of actions of the steering group. Furthermore, effect size analysis suggests that program schools generally showed better development in school quality dimensions compared to comparison schools over the program duration. The mediation model suggests that a higher degree of coordination of action leads to a higher degree of inclusion at the school location on a 3-year longitudinal average. The longitudinal effect of coordination of action on inclusion at the school site can be attributed to the teachers' cooperation for classes. This study contributes significant empirical evidence regarding the effectiveness of a multiple strategy approach for professionalizing school leaders and improving schools in challenging circumstances. It underscores the importance of coherent, long-term, context-specific support strategies. The findings have important implications for identifying conditions for successful implementation of such programs, informing practices for supporting schools in challenging circumstances, advancing the understanding of effective school leadership development, and bridging the gap in research on comprehensive support programs for school leaders in Germany.

Baumert, J., Stanat, P., & Watermann, R. (Hrsg.). (2006). Herkunftsbedingte Disparitäten im Bildungswesen: Differenzielle Bildungsprozesse und Probleme der Verteilungsgerechtigkeit. VS Verlag für Sozialwissenschaften. https://doi.org/10.1007/978-3-531-90082-7 Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2. Aufl.). Erlbaum. Creemers, B. P. M., Peters, T., & Reynolds, D. (Hrsg.). (2022). School effectiveness and school improvement (First edition). Routledge. Darling-Hammond, L., LaPointe, M., Meyerson, D., Orr, M. T., & Cohen, C. (2007). Preparing School Leaders for a Changing World: Lessons from Exemplary Leadership Development Programs. Stanford University, Stanford Educational Leadership Institute. https://wallacefoundation.org/sites/default/files/2023-09/Preparing-School-Leaders.pdf Darling-Hammond, L., Wechsler, M. E., Levin, S., Leung-Gagne, M., & Tozer, S. (2022). Developing effective principals: What kind of learning matters? Learning Policy Institute. https://doi.org/10.54300/641.201 Grissom, J. A., Egalite, A. J., & Lindsay, C. A. (2021). How Principals Affect Students and Schools: A Systematic Synthesis of Two Decades of Research. The Wallace Foundation. http://www.wallacefoundation.org/principalsynthesis Grissom, J. A., & Harrington, J. R. (2010). Investing in administrator efficacy: An examination of professional development as a tool for enhancing principal effectiveness. American Journal of Education, 116(4), 583–612. https://doi.org/10.1086/653631 Gümüş, S., Şükrü Bellibaş, M., Şen, S., & Hallinger, P. (2024). Finding the missing link: Do principal qualifications make a difference in student achievement? Educational Management Administration & Leadership, 52(1), 28–51. https://doi.org/10.1177/17411432211051909 Kovačević, J., & Hallinger, P. (2019). Leading school change and improvement: A bibliometric analysis of the knowledge base (1960–2017). Journal of Educational Administration, 57(6), 635–657. https://doi.org/10.1108/JEA-02-2019-0018 Leithwood, K. A., & Louis, K. S. (2012). Linking leadership to student learning. Jossey-Bass. Rhodes, C., & Brundrett, M. (2009). Leadership development and school improvement. Educational Review, 61(4), 361–374. https://doi.org/10.1080/00131910903403949 Sammons, P., Hillman, J., & Mortimore, P. (with University of London). (1995). Key characteristics of effective schools: A review of school effectiveness research. OFSTED. Teddlie, C., & Stringfield, S. C. (1993). Schools make a difference: Lessons learned from a 10-year study of school effects. Teachers College Press. Young, M. D., Crow, G. M., Murphy, J., & Ogawa, R. T. (Hrsg.). (2009). Handbook of Research on the Education of School Leaders. Routledge. https://doi.org/10.4324/9780203878866