This doctoral study, using a qualitative dominant mixed methods case study design, investigates how the professional development of school-based teacher educators (SBTEs) can promote collaboration between partner schools and universities (Dille, 2023). Collaboration between teacher educator participants can take place in third spaces, which Zeichner (2010) describe as a ‘creation of hybrid spaces in preservice teacher education programs that bring together school and university-based teacher educators and practitioner and academic knowledge in new ways to enhance the learning of prospective teachers’ (Zeichner, 2010, p. 92). Coherence is central to this third space activity and can be strengthened through shared arenas where teacher educators align their visions and goals (Smith, 2016).

Cultural Historical Activity Theory (CHAT) is used to explain coherence in teacher education, emphasizing that learning is affected of its history, occurs in multiple contexts, and is embedded in two or more activity systems (Engeström & Sannino, 2010). Engeström and Sannino (2010) explain division of labour, or who the subjects participate with, into two groups: horizontal and vertical. While a horizontal activity involves tasks where participants are of equal status, a vertical activity reflects asymmetry in their positions. Although both vertical and horizontal activities are important across and within activity systems, vertical approaches place less emphasis on participants as learners in a community (Akkerman & Bruining, 2016). In third space activities, horizontal activity is preferred.

SBTEs play a crucial role in field practice, and their mentoring competence is vital in third spaces (Advisory Panel for Teacher Education, 2020). However, SBTEs often struggle in their role as teacher educators, which is often explained by the fact that the role of Norwegian teachers as SBTEs is a small part of their job, in addition to their main job being teachers for students. Some report challenges with the identity shift from teachers for students to mentors for pre-service teachers (PSTs) (Parker et al., 2021), others feel insecure in this role (Bullough Jr, 2005), and many SBTEs do not identify as teacher educators (Helleve & Ulvik, 2019). Additionally, several SBTEs feel isolated in this role (Nilssen, 2016).

The study highlights that field practice activities are mostly connected to SBTEs’ partner schools. SBTEs use third space activities for their work and professional development, but universities are not active contributors in SBTEs' professional development. The university's main activity can be described as a vertical approach because it mostly delivers information rather than inviting SBTEs to collaborate, leading to a bias towards SBTEs and their partner schools.

The study's findings reveal that "willingness" is the overarching category, which is crucial for SBTEs’ professional development and promoting collaboration between partner schools and universities. Three main categories were identified: engagement (SBTEs’ activities), deliverers (university activities), and connecting (activities which takes place in the hybrid third space). The connecting category was divided into two, capturing activities involving other participants and artifacts. The findings reveal that to strengthen SBTEs professional development through third space activity, three types of willingness are important: willingness to invite (university context), willingness to interact (SBTEs’ engagement), and willingness to be included (third space context). These findings align with previous research, both nationally and internationally.

This study followed a qualitative-dominant mixed methods case study design positioned under a constructivist paradigm. The constructivist paradigm allowed for choosing a partly planned and partly emergent design (Schoonenboom & Johnson, 2017). A case study can be explained as ‘a study that investigates a contemporary phenomenon in depth and in its real-world context’ (Yin, 2014, p. 237). The case in this doctoral study is classified as an abstract case, specifically ‘experiences of professional development’ (Yin, 2014). Positioning under a social constructivist paradigm and using Cultural Historical Activity Theory (CHAT) as the theoretical framework allowed the researcher to take an active role in the research process. The results present the researcher’s perceptions of reality, not reality itself (Postholm & Jacobsen, 2018). The study embraces Lincoln and Guba's (1985) four criteria for trustworthiness: credibility, transferability, confirmability, and dependability. Despite being limited to a single university, the two teacher education programs have SBTEs located in about 100 partner schools, providing insights into contextual complexities suitable for case studies (Yin, 2014). The study sample consisted of SBTEs with dual roles as SBTEs for PSTs and teachers for students in primary and lower secondary schools. Substudy samples were selected using three strategies: homogenous sampling, purposeful sampling, and scoping process. 242 SBTEs participated in the survey, 21 SBTEs completed the OTPD program, and 52 studies were included in the scoping process. A mixed methods design was chosen to compare different perspectives from quantitative and qualitative data (Creswell & Creswell, 2018). Data were collected using "between strategies," which ‘involves the gathering of both QUAL and QUAN data using more than one data collection strategy […].’ (Teddlie & Tashakkori, 2009, p. 2018). Three main data sources were used: 1) a scoping review mapping existing studies (Arksey & O’Malley, 2005). 2) reflective diaries from OTPD program participants, described as ‘containers for writing that provides students with a framework to structure their thoughts and reflections’ (Wallin & Adawi, 2018, p. 511). The diaries allowed participants to reflect on their beliefs and values and connect their experiences with goals; 3) a survey with eight sections, mostly involving a five-point Likert scale. An abductive approach was chosen for analyzing the main research question, enabling the researchers to go back and forth with the data material, comparing wholes and parts during the research process (Alvesson & Sköldberg, 2008).

This study highlights that professional development among school-based teacher educators (SBTEs) can promote collaboration between partner schools and universities. The findings revealed a bias in activities between partner schools and universities, with SBTEs mentoring pre-service teachers (PSTs) at their schools but having limited contact with universities. The dissertation emphasizes the need for universities to be more than just information providers and to actively engage in field practice collaboration. There remains a gap between the intended and actual collaboration between universities and partner schools. The primary empirical contribution is an enhanced understanding of SBTEs’ experiences with coherence in third spaces. The results show that national guidelines alone are insufficient to ensure coherence; individual field practice still plays a significant role. Willingness to invite, interact, and include others is crucial for activities in third spaces, involving both vertical and horizontal collaboration. A facilitator is essential for organizing vertical activities, while peer collaboration exemplifies horizontal activities. The dual roles of SBTEs as both teachers and mentors present challenges. OTPD programs can serve as boundary artifacts to strengthen connections between learning arenas, but technological tensions must be addressed. Physical meetings at universities are important for fostering online collaboration among SBTEs from different schools. The study found that both facilitators and school leaders should encourage and promote collaboration among colleagues. The study's implications are mainly related to the institutional level. Universities and partner schools need to align their practices to develop field practice in teacher education. Political implications are also central. Financial support for mentoring education is crucial, as many SBTEs do not prioritize it due to a lack of funding. Leaders who support and fund mentoring education can contribute to better-qualified SBTEs and improved field practice for PSTs. The study's findings align with international research, suggesting broader political implications.

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