School middle leadership: A systematic review

Abstract

School middle leadership is a complex and increasingly important school leadership position, with research showing the significance of middle leadership to school improvement and teacher development. The purpose of this article is to identify and analyse empirical peer reviewed articles on middle leadership from 2006 to 2020, to understand how middle leaders are defined, the responsibilities they hold, the impact and professional development they are afforded, and to discover lacunae in studies to support further research. The review was conducted using Scopus and ERIC; a total of 35 articles across 14 countries were selected. Using Nvivo, narrative synthesis was utilised to analyse the articles resulting in four conclusions: 1) middle leadership is difficult to define; 2) middle leadership positions and responsibilities vary considerably and are best understood in context; 3) middle leaders directly and indirectly impact teacher practice, team development, school reform and professional learning, although there is limited direct research into their impact; and 4) middle leadership professional learning has not progressed to the point to adequately equip middle leaders for the complexity of their positions. The article highlights two distinguishable differences to separate teachers and middle leaders, and provides an operational definition, elaborated description and set of middle leadership characteristics to guide future research and policy advancement.

Keywords

Middle leadership teacher leadership curriculum leadership professional development distributed leadership systematic review

Introduction

School leadership is acknowledged as critical for school improvement (Leithwood et al., 2020; Robinson et al., 2008). Principals are recognised as playing an important role in school effectiveness, teacher quality and student achievement (Dinham et al., 2011). While the practices of leaders are shaped by cultural, political and institutional factors, it is generally accepted that principals lead school improvement by establishing the school vision, creating safe and orderly environments, and providing overall direction and conditions for teachers as instructional experts (Bryk and Schneider, 2002; Leithwood et al., 2020; Robinson et al., 2008). Importantly, principals lead school improvement by sharing leadership with others (Urick and Bowers, 2014). Distributed leadership – an approach to collective, shared and dispersed forms of leadership and influence – is shown to support schools to meet increasing demands (Harris and DeFlaminis, 2016) and support leaders and educators’ collective contribution and influence to school improvement (Elmore, 2000).

Middle leaders (MLs) operate at the interface between different sources of influence and change within the school. While they are not responsible for the overall organisation of the schools, they are ‘key brokers within organisations’ (Earley and Bubb, 2004: 162) and significant actors in distributed leadership approaches to school improvement (Lárusdóttir and O’Connor, 2017). Middle leadership is different to principalship as MLs do not have organisational responsibility for all components of school function (Murphy, 2013). However, their positioning of leadership close to the classroom affords them opportunities to lead teaching and learning from the core site of a school. There are inherent challenges for MLs as ‘brokers’ as they attempt to work between principals and teacher colleagues. The findings from this review draw attention to certain leadership dichotomies such as support and monitoring, and leading and managing and what conditions are necessary to support MLs to work within these tensions.

The advancement of understanding the significance of middle leadership has resulted in increased attention by educational researchers who want to understand the shifts and complexities in this important leadership space (Gurr, 2019). DeNobile (2018) developed a theoretical model of middle leadership based on his review of 250 journal articles, conference papers and leadership reports. The Middle Leadership in Schools (MLiS) model provides an overview of the different roles, factors, influences and impacts of middle leadership. DeNobile (2018) suggests further empirical work is required to investigate theoretical constructs and relationships between roles, practices and impacts. Our review focusses on impact and reveals that MLs have the potential to impact in four predominant ways.

Forde et al. (2019) investigated national policy developments for MLs in Scotland and Ireland. They found that policy in both countries has evolved from a focus on management to leadership. However, Forde et al. (2019) caution that middle leadership is in danger of becoming task orientated and driven by top-down policy where MLs are simply conduits to policy reform. They suggest a move away in policy from a focus on middle leadership roles and tasks to a greater focus on the middle leadership practices associated with leadership of teaching and learning.

This article first provides an overview of previous literature reviews, then summarises existing findings on teacher leadership and middle leadership to highlight useful insights and the significance of this review. We then describe our methodology, followed by a systematic review of the literature in relation to middle leadership definitions, responsibilities, impacts, professional development opportunities and needs. We conclude by presenting recommendations for future research.

Previous reviews

In addition to the research discussed in the introduction, it is important to recognise previous systematic literature reviews into teachers as leaders. These reviews examine middle leadership to some degree, and each one offers critical insights. York-Barr and Duke (2004) reviewed 100 empirical studies in teacher leadership over 2 decades (1980 to 2004). They conclude that teacher leadership is ill defined and offer a framework to guide future inquiry. Wenner and Campbell (2017) updated York-Barr and Duke’s (2004) review by examining 54 documents situated in K-12 schools between 2004 and 2013. This review focused on teacher leadership, impacts, conditions and theories and found no research that examined the impacts of teacher leaders on student learning. Similar to York-Barr and Duke (2004), the findings from the Wenner and Campbell (2017) review highlighted the difficulties in defining teacher leadership, the important roles of principals, structures and norms in enabling teacher leaders to lead effectively, and common constraints of lack of time and overwhelming workloads.

Nguyen et al. (2019) examined 150 empirical studies published between 2003 and 2017 to uncover contextual and methodological considerations in teacher leadership. While completed at a similar time to Wenner and Campbell (2017), Nguyen et al. (2019) adopted a broader conceptualisation of teacher leadership, in which teachers not only lead beyond the classroom, as defined by Wenner and Campbell (2017), but also within the classroom. Unlike Wenner and Campbell (2017), Nguyen et al. (2019) examined the indirect relationship between teacher leadership and student learning. Similar to research cited above, Nguyen et al. (2019) concluded that teacher leadership is difficult to define and that small-scale qualitative studies continue to dominate research in this field. Schott et al. (2020) reviewed 93 studies on teacher leadership published between 2014 and 2018 to investigate definitions, antecedents, outcomes and methodological quality. Similar to Wenner and Campbell (2017), they argue teacher leadership is still undefined. They highlight the limitations of teacher leadership research, which often examines single sites and uses single methodologies. It is important to note that the terms ‘middle leadership’ and ‘leaders’ were not used as search terms in the above literature reviews.

Bennett et al. (2007) disseminated the findings of two reviews which collectively examined 152 studies focused on subject leaders in secondary schools between 1988 and 2005. The studies reviewed by Bennett et al. (2007) were not exclusively focused on middle leadership; rather, they focused on ‘the role of teachers who had non-teaching responsibilities but were not seen as senior members of staff’ (454). The authors identified two key challenges. The first is the expectation that MLs will lead effectively both at the school level and in their own departments (usually a curriculum area) whilst remaining loyal to the department and their colleagues. The second is the system of accountability in which MLs are focused on relationships with teacher colleagues but are responsible for monitoring colleague teacher quality. Bennett et al. (2007) found these tensions led to three overall findings: 1) MLs prefer collegial team-based approaches to leadership; 2) MLs see teachers as professional, autonomous and equal in schools, so they avoid monitoring and performance-managing teacher colleagues; and 3) MLs are often chosen due to their subject knowledge and teaching expertise. It is this expertise, rather than preparation for their formal leadership roles, that is the source of their authority. While this comprehensive review provided some clarity about MLs’ practices, challenges and contexts from research published over 15 years ago, recent middle leadership researchers (Gurr and Drysdale, 2013; Lipscombe et al., 2020a) note that middle level leadership requires increased and contemporary research.

More recently, Harris et al. (2019) completed a bibliometric analysis of 49 articles in middle leadership between 2003 and 2017, including studies in which middle leadership was secondary to a broader research topic. They found that since 2003 there has been more, but not dramatically more, interest in empirical research into middle leadership, with most articles using qualitative methodologies. Harris et al.’s (2019) findings helped to quantify available empirical literature in middle leadership by providing important information about, for example, the frequency and methodologies of middle leadership research.

The six studies discussed above collectively review documents from 1980 to 2018 and contribute important understandings of teacher leaders and MLs who lead both within and beyond the classroom. Previous studies have highlighted definitions, theoretical frameworks, and the impacts of teacher leadership. However, they do not focus on or include empirical studies specifically on middle leadership. Bennett et al. (2007) reviewed studies from a range of fields which examined leaders who led but were not senior leaders, and the research was conducted over 15 years ago. This is problematic in today’s context due to changes in educational policy, with middle leadership roles evolving from teachers being heads of faculty, to being middle managers with administrative duties, and more recently to being leaders of teaching and learning and school improvement. The bibliometric review by Harris et al. (2019) did not report or analyse the findings of the literature reviews, with the authors suggesting that future reviews of such literature would be useful. Importantly, none of the six studies include a systematic review of school middle leadership, the focus of this study.

Present study

In consideration of previous studies and the increased research and practical interest in middle leadership, there are two key motivations for this study. The first is the gap between interest in middle leadership and the advancement of research into teachers who are MLs. An examination of previous systematic literature reviews shows research into teacher leadership is far more advanced than research into middle leadership. The second motivation relates to the acknowledged importance of middle leadership for improving school teaching and learning (Gurr, 2019) and the international trend of increasing shortages of school leaders (Rhodes and Brundrett, 2009). Due to these trends, middle leadership development is seen as an important driver for leadership retainment and school improvement. This review can contribute to an understanding of school leadership by investigating the following research questions:

How is school middle leadership defined?

What are the positions and responsibilities of school MLs?

What is the impact of middle leadership in schools?

What are the professional development opportunities and needs of school MLs?

Systematic literature review methodology

This systematic literature review used two search databases: Scopus and ERIC (ProQuest). Scopus was chosen as the largest citation and abstract database of peer-reviewed literature covering arts and humanities, medical, scientific, social sciences and technical literature, and ERIC was chosen as it is the world’s most widely-used index for educational literature. The literature review spanned from January 2006 to January 2020. This time frame was chosen to build on Bennett et al.’s (2007) review from 1998 to 2005, and to provide a comprehensive understanding of empirical research that has been completed over the last decade in the context of significant changes to educational policy and accountability measures impacting schools.

The review employed a comprehensive research protocol to ensure transparency and rigour (Jesson et al., 2011). The protocol included the following six processes: define the research question/s; identify key words and databases; conduct a comprehensive literature search; apply inclusion and exclusion criteria; critically appraise the sources in regard to academic rigour; and synthesise the findings of the studies. A preliminary exploratory literature search demonstrated that the ‘middle leadership’ concept is associated with a range of terms in a variety of contexts. To ensure the search focused solely on MLs in schools, the following keywords were used:

‘middle leadership’ AND education; ‘middle leadership’ AND school

‘middle leading’ AND education; ‘middle leading’ AND school

‘middle leaders’ AND education; ‘middle leaders’ AND school

‘leading from the middle’ AND education; ‘leading from the middle’ AND school

‘middle-level leadership’ AND education; ‘middle-level leadership’ AND school.

Screening

Studies included in this review are empirically-based English language peer reviewed journal articles. The findings reported are from original (not descriptive) studies written in English where middle leadership is central, and the research is based in schools (not early childhood or higher education settings). As the literature review focused on the construct of middle leadership, teacher leadership-focused research was excluded.

Table 1 below highlights the search progress through the databases based on the inclusion and exclusion criteria. The review was a multi-stage, iterative review of the research literature. After secondary screening, 35 articles were retained representing research in middle leadership across 14 different countries. A list of these articles is available as a supplementary document.

Table 1.

Article screening.

Database search 2006–2020	N=275
Disregard duplicated	Disregard n=165
Articles retained	n=110
Disregards after scan of abstract	Disregard n= 62 Reasons: Middle leadership was peripheral to the article n=38 Was not situated with schools n= 21 Descriptive, not empirical n=3
Articles retained	n=49
Read through entire articles	Discard n= 14 Reasons: Middle leadership was peripheral n=4 Article could not be located n=1 Research not situated in schools n= 7 Article was not peer reviewed n=2
Articles retained	n= 35

Data analysis

The data was analysed by conducting a narrative synthesis of the reviewed material. This approach enabled the researchers to use words and phrases from the selected empirical studies to synthesise a large amount of information from multiple sources in a way that enabled conclusions to be drawn rather than simply providing a summary of information (Popay et al., 2006). Data analysis was conducted using spreadsheets and NVivo 12Plus. First, each study was tabulated to represent its key characteristics (methodology, date, origin). Using NVivo, studies were then clustered according to research questions where line-by-line coding was completed within broader categories that addressed the research questions. These broader categories were then subjected to a secondary round of coding that identified specific themes found within the research questions. Lastly, an exploration of the relationships between findings was completed, which is reported in the results and discussion sections. To reduce research bias, three coders initially coded all articles independently. In the second round of coding, the two lead researchers coded the first three articles together so that the subsequent second round of coding was completed the same way. As the selected articles included various methodological approaches and spanned across 14 countries, several strategies were used to take into account these differences including: extracting contextual details as part of data extraction; reporting on contextual characteristics where appropriate; and reporting contextual details in supplemental materials for readers to review in consideration of results (Booth et al., 2019). While this study is not aimed at examining potential explanatory factors from different countries, considerations relevant to various contexts were considered. The researchers found no significant themes to describe different implications. Although the review followed a rigorous process, the results should be approached with caution. Terms associated with middle leadership such as ‘Head of Department’ were not included within the search terms in this study. Additionally, the review focused on empirical research articles only. Further research could extend the search terms and source types in order to obtain a broader picture.

Results

In this section, the results of the reviews are discussed in relation to the research questions.

How is school middle leadership defined?

A teacher with formal leadership responsibilities is the most commonly used characteristic to explain the position of a ML. While most scholars agree that MLs have formal leadership responsibilities, there is disagreement about the significance of their teaching responsibilities. Australian research from Edwards-Groves et al. (2016), Grootenboer et al. (2015), and Gurr and Drysdale (2013) argues that MLs must hold formal leadership responsibilities and significant teaching responsibilities. For example, a Head of Science may teach for 70% of their time and be provided with the remuneration and responsibilities to lead science across the school. Research from other countries stops short of suggesting MLs must have significant teaching responsibilities. According to Heng and March (2009) MLs in Singapore are teachers that take on management and pedagogical responsibilities but they stop short of suggesting that MLs necessarily have significant teaching loads. Similarly, Li et al.’s (2018: 2) definition in a study situated in England does not include teaching as a characteristic and instead suggests school MLs ‘are those who assume formal responsibilities and duties of leadership and management at a level situated between the principal and teachers’ (2). Li et al. (2018) include middle leadership positions in areas of pastoral care such as career guidance and counselling. Such examples highlight roles that may not include teaching responsibilities. At a definitional level it is unclear whether full-time pedagogical coaches who are solely responsible for teacher development, as seen in some schools in Australia, are MLs. Instead of the dual roles of classroom teacher and leader, they lead teacher development without classroom teaching responsibilities.

Commonly, scholars also define middle leadership by positionality (Grice, 2019; Grootenboer et al., 2015; Gurr, 2019; Li et al., 2018; Ng and Chan, 2014; Tay et al., 2019). Much of this work can be traced to Grootenboer et al. (2015) who explains that MLs are typically positioned between senior leaders and teaching staff, and practise leading through their membership of both groups.

Similar to positionality, but not as frequently discussed, is the constitution of the subcultures MLs work in. While the positionality of MLs is often referred to as a ‘position’ or ‘post’ within a hierarchical organisational structure (Bassett and Shaw, 2017; Irvine and Brundrett, 2019; Ng and Chan, 2014), middle leadership is defined as involving more than occupying an ‘in between’ positional space. MLs are often described as working alongside their colleagues while at the same time working ‘up’ to senior leadership (Edwards-Groves et al., 2016; Grootenboer et al., 2015). They frequently lead in one context and follow in another, and as such inhabit more than one community or subculture (Grice, 2019; Irvine and Brundrett, 2016).

The notion of accountability is used to describe middle leadership although what they are accountable for, and who they are accountable to, differs across studies. Some discuss accountability as line management to principals (Bryant, 2019; Farchi and Tubin, 2019) and colleagues (Fitzgerald, 2009; Gurr 2019). Others discuss accountability of responsibilities, for example, teacher performance (Hall, 2018) and professional learning (Edwards-Groves et al., 2019). Hall (2018) suggests that MLs’ accountability for teacher performance can be attributed to external performative measures, however Heng and Marsh (2009) argue that external accountability should be replaced with ‘professional accountability’ focussed on internal capacity building of colleagues. What seems evident is that MLs are commonly accountable to their principals for the responsibilities they lead while also being mutually accountable with colleagues for teacher quality and development. Edwards-Groves et al. (2019) suggest that this mutual accountability orients professional learning as a shared endeavour.

Distinguishing middle leadership from teacher leadership

There is some agreement that middle leadership is distinct from teacher leadership, although there is also evidence that the boundary between these two school leadership spaces is blurred. Our analysis has identified some distinguishable differences.

Perhaps due to the newness of the field or the commonalities between the two constructs, much of the middle leadership research draws on teacher leadership research. For example, Gurr and Drysdale (2013) suggest that defining middle leadership is complex, and their own definition is aligned with the definition of teacher leadership in an Organisation for Economic Co-operation and Development (OECD) report (Schleicher, 2012). Bassett and Shaw (2017) use teacher leadership research by Struyve et al. (2014) to help explain middle leadership. Irvine and Brundrett (2019) draw on teacher leadership research from Crowther et al. (2009). Others have hinted at a distinction between middle leadership and teacher leadership. Grootenboer et al. (2015: 509) acknowledge that middle leadership is not the same construct as teacher leadership, which is ‘more generic and ubiquitous’, while Grice (2019: 176) suggests that MLs are not ‘rebadged teacher leaders’. Heng and Marsh (2009) explain more directly the definitional difference between the two constructs, suggesting middle leadership is conceptually aligned to teacher leaders, however, they argue that middle leadership is a narrower construct as it encompasses only formal school leadership positions with designated responsibilities, in contrast to teacher leadership that encompasses the broader capabilities of teachers who lead informally within their schools. Similarly, Bryant and Rao (2019) suggest teacher leaders lack position and instead lead through influence.

What appears to be a critical difference between teacher leadership and middle leadership is the formalisation of MLs’ roles and the level of accountability involved. This is supported by previous reviews in teacher leadership (Bryant and Rao, 2019; Nguyen et al., 2019; Wenner and Campbell, 2017) that refer to teacher leadership as involving influence rather than formal authority. This suggests that teacher leaders may not have formal role descriptions, policies or processes to support or inform their work. In contrast, definitions of MLs’ roles invariably make explicit the position of MLs in the school hierarchy (Grootenboer et al., 2015; Gurr and Drysdale, 2013). They are often described in terms of their line management (Ng and Chan, 2014), accountability to stakeholders (Irvine and Brundrett, 2019), and direct responsibilities (Koh et al., 2011). A formalised leadership position, and accountability for leadership responsibilities, appear to be two key characteristics that distinguish MLs from teacher leaders.

What are the positions and responsibilities of school MLs?

This review highlights the vast and expanding range of positions MLs now occupy in schools. This may be attributed to the increasing number of leadership positions in schools resulting from the intensification of school administrative and compliance responsibilities, coupled with a greater focus on school improvement. Importantly, findings from the review suggest MLs’ responsibilities are typically situated within certain dichotomies such as collegial support and performance, and leading and managing responsibilities.

Expanding middle leadership positions

While Bennett et al.’s (2007) review focused almost exclusively on subject leaders, the articles in this review indicate that since 2006 MLs’ positions have expanded beyond subject leadership. Table 2 overviews empirical studies where participants in middle leadership positions are clearly identified. It is important to note that many of the studies reviewed did not identify MLs clearly by position. Although Table 2 is not exhaustive, data suggests that middle leadership positions include curriculum, pastoral, subject and pedagogical leadership positions with responsibilities predominantly at the team and school level, although some researchers do suggest ways MLs lead beyond the team or the subject they lead (Bryant and Rao, 2019; Gurr and Drysdale, 2013).

Table 2.

Middle leadership positions in empirical studies.

Middle leadership positions	Sources
Subject head / leader / coordinator / leaders	Bassett, 2016; Bryant, 2019; Farchi and Tubin, 2019; Grice, 2019; Gurr, 2019; Heng and March, 2009; Li et al., 2018; Turner and Sykes, 2007
Heads of department / faculty	Bassett, 2016; Fitzgerald, 2009; Hall, 2018; Heng and March, 2009; Jarvis, 2008; Javadi et al., 2017; Shaked and Schechter, 2017; Tay et al., 2019
Curriculum coordinators / leader	Bassett and Shaw, 2017; Gurr, 2019
Pastoral leaders	Gurr, 2019
Year/ stage coordinators / heads / advisers	Gurr, 2019; Lipscombe et al., 2020a; Shaked and Schechter, 2017; Tay et al., 2019; Turner and Sykes, 2007
Head / lead teachers	Hirsh and Segolsson, 2019; Thorpe and Bennett-Powell, 2014
Pedagogical coach	Grice, 2019
Team leader	Bassett and Shaw, 2017
Director of learning / teaching	Bryant and Rao, 2019; Grice, 2019

Collaboration and performance management responsibilities

The findings reveal that increased accountability, resulting in the performance management of colleagues, is a significant and complex responsibility for MLs. This responsibility results in tensions between being supportive, collaborative colleagues and being quality assurers and monitors of teacher colleagues’ performances (Grice, 2019; Hall, 2018; Heng and March, 2009). This conflict has previously been noted by Bennett et al. (2007) who found MLs’ preferences were for an informal approach to management of colleagues rather than a formalised one. Cardno and Robson (2016: 230) explain that teacher performance responsibilities involve a ‘vertical chain of command’, where MLs are expected to report on the performance of their colleagues to senior leaders while also working collegially with them. This creates an inherent challenge, with researchers such as Thorpe and Bennett-Powell (2014) and Koh et al. (2011) highlighting the tension between MLs supporting, motivating and developing staff, and monitoring staff performance.

Clearly, for MLs to impact school teaching and learning practices, they need to collaborate with teachers and not just be conduits between teachers and senior staff or take on the responsibilities of staff supervisors (Bryant and Rao, 2019). One contrasting finding comes from Javadi et al. (2017), who report that in private Malaysian international schools, where accountability and fees are heightened, MLs tend to align more closely with senior leaders than with teacher colleagues.

Leading and managing

While the findings highlight the tension between middle leadership responsibilities of support and monitoring, they also draw attention to a tension between management and leadership. Within the research there is an increasing expectation from school systems and leaders that MLs will lead as well as manage (Bassett, 2016; Bryant, 2019; Farchi and Tubin; 2019). The reviewed research indicates MLs now typically engage in an array of managerial responsibilities (e.g. managing budgets, timetables, reporting) and leading (e.g. mentoring, facilitating professional development). This shift has been attributed to the redistribution of school leadership (Bryant, 2019; Hirsh and Segolsson, 2019; Lipscombe et al., 2020b), the devolution of authority to schools (Fitzgerald, 2009; Heng and Marsh, 2009), an increased focus on school improvement (Grice, 2019; Grootenboer and Larkin, 2020; Koh et al., 2011; Thorpe and Bennett-Powell, 2014) and school compliance (Hall, 2018).

Managing and leading are different but complementary practices that MLs enact, and while there may be an expectation of MLs leading above managing (Bennett et al., 2007; DeNobile, 2018), this review found a somewhat different reality. Bassett and Shaw (2017) found New Zealand (NZ) MLs placed primary importance on their teaching roles. They found administrative roles time consuming, and when coupled with a lack of confidence, leadership was not prioritised. Also, in New Zealand, Fitzgerald (2009) found that MLs’ responsibilities were dominated by management tasks, leaving little time for leadership. Jarvis (2008: 29) reports that teachers felt their MLs managed rather than led, with school MLs being an ‘under-utilized leadership resource’. Javadi et al. (2017) found MLs’ responsibilities lacked clarity, leading to management rather than leadership in learning. MLs often view themselves as managers rather than leaders and perceive their role as ‘more positional than influential’ (Lárusdóttir and O’Connor, 2017: 435).

The research shows if schools and school systems want MLs to lead rather than manage, there are conditions which facilitate this, including an ethical school culture founded on respect and trust (Edwards-Groves et al., 2016; Fitzgerald and Gunter, 2006), autonomy and respect for teachers’ professionalism (Fitzgerald and Gunter, 2006), school-wide collegial relationships (Edwards- Groves, et al., 2019), and principal and school executive conditions which support leading (Grootenboer et al., 2015; Grootenboer and Larkin, 2020; Gurr, 2019) with MLs provided the necessary time, space and legitimate authority (Fitzgerald and Gunter, 2006). Farchi and Tubin (2019) argue that it is only when management practices become seamless that MLs are able to lead school teaching and learning reform. Further to optimising middle leadership working conditions to support leading over managing, there is an evident need for targeted middle leadership professional learning, which is discussed later in the article.

What is the impact of middle leadership in schools?

The impact of middle leadership is of great interest. It is argued that MLs have the potential to impact school improvement (Bryant, 2019; Gurr and Drysdale, 2013), particularly in teaching and learning (Bassett, 2016; Gurr, 2019; Gurr and Drysdale, 2013). To understand the prevalence and nature of MLs’ impacts, articles whose aims and research questions focused on those impacts were reviewed. Of the 35 articles, 7 purposely identified that they investigated MLs’ impacts (see Table 3) although the way impact is interpretated across the articles varies in terms of how impact is measured, and the scope, level and the durability of impact. Additional details about each of these studies are available in the supplemental material.

Table 3.

Middle leadership impact in research studies, 2006–2020.

Source	Research aim and or research question(s) (RQ) relating to impact	Major middle leader impact finding(s)
Bryant et al. (2020)	Aim: Investigates MLs’ development of others’ professional and leadership capacities. RQ: How do MLs enact their potential as builders of in-service teachers’ capacity?	Evidence of MLs building teachers’ capacities both directly and indirectly.
Bryant and Rao (2019)	Aim: Analyse the influence of teacher leadership on the enactment of educational reforms in South Eastern China RQ: What contributions do MLs and teacher leaders make in enacting reforms?	Evidence of MLs influencing school reform.
Edwards-Groves et al. (2019)	RQ: What is the influence of the MLs on site-based education development in primary schools?	Indirect evidence of MLs’ practices that create conditions to support school reform.
*Gurr (2019)	Aim: To investigate the role perception and the differences in these perceptions across senior leaders, MLs and teachers, and the perceived effects of MLs, especially related to school improvement, and supports and barriers.	Evidence across 6 case studies of MLs impacting teaching and learning in curriculum and indirectly impacting student learning outcomes through building teacher capacities, school improvement strategies, culture and vision.
Jarvis (2008)	Aim: Identify the influence of heads of department on the classroom practice of those they lead.	Evidence of MLs’ indirect impact on teachers’ motivation and/or morale
Koh et al. (2011)	Aim: Provide a rich description of the leadership role of MLs as perceived by school leaders.	Evidence of MLs’ direct impact on building teacher capacities through professional learning and influencing school vision.
Li et al. (2018)	Aim: Examine how the interplay of middle leadership and other contextual factors impacts on implementing system-wide English language curriculum reform.	Direct evidence of MLs’ impact on building teacher capacities.

*Gurr (2019) article includes the three research studies reported by Gurr and Drysdale (2013)

Our review reveals that the identification of middle leadership impact is ambiguous. Six of the seven studies made claims of indirect impact in areas such as teacher practices (Bryant et al., 2020; Gurr 2019) team development and interactions (Bryant et al., 2020), school reform (Bryant and Rao, 2019), and professional learning (Edwards-Groves et al., 2019; Koh et al., 2011; Li et al., 2018). Worthwhile noting is that impact in these studies is often described by MLs’ ‘perception’, ‘involvement’, ‘role’, ‘expectation’ and ‘contribution’. Li et al. (2018), through survey and factor analysis, claim direct middle leadership impact in areas of teacher pedagogy, teacher participation in system-wide professional learning and receptivity towards school reform and student learning. In a study by Jarvis (2008), as a result of heavy managerial responsibilities, MLs impact is seen as a ‘missed opportunity’ (29) as a result of heavy administration burdens.

The way MLs impacted on the areas stated above was associated with strategies such as developing communication structures (Bryant et al., 2020), cross-disciplinary collaboration across the school such as team meetings (Bryant et al., 2020), planning, designing and aligning curriculum (Gurr, 2019), building collegial relationships including brokering between principal and teachers (Edwards-Groves et al., 2019; Koh et al., 2011), role modelling and innovation of teaching practices (Koh et al., 2011), coaching and mentoring (Gurr, 2019), and positively influencing teachers’ perceptions and participation (Li et al., 2018).

Importantly, while claims are made about middle leadership impact in the seven studies, most are indirect (Bryant and Rao, 2019) and based on perceived or potential impact (Bryant et al., 2020; Gurr, 2019; Jarvis, 2008). As elaborated in the discussion section, no reviewed studies provided direct evidence of causal relationships related to the impact of middle leadership on teacher practice and effectiveness or student learning practices or outcomes.

What are the professional development opportunities and needs for school middle leaders?

In the reviewed literature, there is an inherent tension in the field of professional development. On one hand, and most commonly, it is argued that MLs are significant facilitators of the professional learning of others (Bryant et al., 2020; Edwards-Groves et al., 2016; Grootenboer et al., 2015; Koh et al. 2011; Lipscombe et al., 2020b; Willis et al., 2019). On the other hand, but less obviously, there is the argument that MLs lack opportunities for their own professional leadership development (Bassett, 2016; Bassett and Shaw, 2017; Gurr and Drysdale, 2013; Thorpe and Bennett-Powell, 2014). We focus on the latter: specifically, we examine the opportunities for MLs’ professional development, and what they need. Our review identifies that MLs’ leadership development opportunities are limited, and that professional development should consider the diverse positions and responsibilities across school sites.

Despite the recognition of the importance of professional development for MLs, the available research suggests a paucity of both experience and development opportunities (Bassett 2016; Bassett and Shaw, 2017; Gurr and Drysdale, 2013). Bassett (2016) and Bassett and Shaw (2017) examined professional development in middle leadership in New Zealand. They concluded that the majority of MLs received some type of leadership development, although many felt inadequately trained and learned through trial and error rather than through formal planned leadership development. Similarly, Bassett and Shaw (2017) suggest there are limited opportunities for New Zealand MLs to engage in professional development. Consequently, aspiring MLs receive limited training before appointment and often rely on an apprenticeship model once in their position. Gurr and Drysdale (2013) reported on three studies from Australia and found that not only were there limited training opportunities for MLs, but many MLs themselves neglected to see the need for professional development.

Middle leadership requires specific skills different to those needed by teachers (Irvine and Brundrett, 2016) or principals (Grootenboer et al., 2015), resulting in a need for continuous professional development opportunities tailored to middle leadership (Donitsa-Schmidt and Zuzovsky 2018; Thorpe and Bennett-Powell, 2014). Bassett and Shaw (2017), Gurr and Drysdale (2013) and Ng and Chan (2014) recommend a repertoire of internal and external professional development opportunities including induction, mentoring and shadowing, with senior leaders identified as being central to middle leadership professional development. Gurr and Drysdale (2013) recommend a proactive, senior leadership approach where principals promote and support MLs through a collaborative culture, organisational policies, structures and processes. Bassett and Shaw (2017) suggest internal development programmes co-designed by principals and MLs that are focused on both school and individual needs. Gurr and Drysdale (2013) and Lárusdóttir et al. (2017) identify a need for principals to engage in their own professional development to support middle leadership development in their schools.

This review suggests that MLs’ professional development should include a focus on: leading teaching, learning and curriculum (Gurr and Drysdale, 2013; Koh et al., 2011; Thorpe and Bennett-Powell, 2014); management (e.g. crisis management, legalities, resource management) (Koh et al., 2011; Ng and Chan, 2014); and capacity building in the individual, professional, organisational and community domains (Gurr and Drysdale, 2013).

Discussion

The purpose of this review was to summarise existing empirical studies and discover lacunae in school middle leadership studies to support further research. We highlight that previous researchers have established school middle leadership as an important and evolving leadership space, with new possibilities for more empirical research. Thirty-five research articles across 14 countries were analysed in consideration of 4 aspects of middle leadership: definitions; positions and responsibilities; impact; and professional development. The results indicate middle leadership is defined by a variety of characteristics, positions and responsibilities, with limited direct research into impact and professional development. What follows is a discussion of four salient implications from this review that can contribute to future research: operational definition, context, impact and professional development. Our findings, and the associated implications, are represented in themes in Figure 1. Important to note is that these themes have varying degrees of empirical evidence to support them, and are situated across various contexts including countries, and school systems and sites, hence caution is required with interpretation of results.

Figure 1.

Overview of research findings and their implications for school middle leadership, 2006–2020.

Middle leadership is best understood within context

Like others, we argue that in research and practice middle leadership is best understood as a social construct which varies according to context and those who experience it. Studies in this review suggest that MLs' responsibilities are most commonly shaped by the school contexts of principal support (Farchin and Tubin, 2019; Grootenboer and Larkin, 2020; Hirsh and Bergmo-Prvulovic., 2019; Javadi et al., 2017); school culture and relationships (Grootenboer et al., 2015; Irvine and Brundrett, 2016; Leithwood, 2016); distribution of leadership (Javadi et al., 2017; Lárusdóttir and O’Connor, 2017); role descriptions (Gurr and Drysdale, 2013; Lipscombe et.al., 2020b); teacher collaboration (Bryant and Rao, 2019; Lipscombe et al., 2020a, 2020b); professional trust (Edwards-Groves et al., 2016), and teaching and learning reforms (Bryant and Rao, 2019; Gurr, 2019). To enable MLs to lead rather than merely manage, and to enable them to impact teacher and student learning, the conditions in which MLs work need to be optimised in reference to the contextual factors highlighted above.

Operational definition, description and characteristics of school middle leadership

Partly due to the importance of context, educational leadership continues to be a highly contested and ambiguous field (Lakomski et al. 2016). The review has uncovered middle leadership is no exception and is complex, diverse and problematic to define. Consequently, many studies choose either not to define the field (Bennett et al., 2007; Hall, 2018; Jarvis, 2008) or to rely on literature in teacher leadership to support explanation (Bassett and Shaw, 2017; Gurr and Drysdale, 2013; Irvine and Brundrett, 2016).

Our review found that middle leadership is distinct from principalship and that teacher leadership and middle leadership, although sharing commonalities, are not interchangeable constructs. Interestingly, while these three leadership positions are distinct, studies also highlight similarities in constraints such as lack of time, unmanageable workloads and increased administration (Bassett, 2016; Bryant, 2019; Riley, 2014; Wenner and Campbell, 2017).

This review provides some clarity in the distinction between middle leadership and teacher leadership by distinguishing two distinct differences: MLs most commonly have formalised leadership positions while teacher leaders do not, and as such MLs are often formally accountable for the leadership responsibilities they hold. The review also highlights that while research and policy have to some extent defined middle leadership, there remains ambiguity, with some scholars calling for further development and commitment to empirical, theoretical, philosophical and developmental work in order to provide empirical warrant for the concept of middle leading (Grootenboer et al., 2015).

We suggest that school middle leadership should be elevated to a definitive concept. This would support MLs, principals, policy makers and researchers to navigate and advance practical and scholarly work in this field. Based on the review findings, we present an operational definition, elaborated description and a set of characteristics of middle leadership. The definition provides a short boundary of meaning to discern middle leadership as a definitive leadership position different to principal or teacher leaders. The description elaborates on the definition and is followed by the five key characteristics of middle leadership drawn from this review (see supplemental material for source references). The definition, description and characteristics acknowledge and value the nuances of middle leadership in previous research over the last decade and will invariably be progressed and elaborated as greater empirical work unfolds.

Definition: School middle leaders are formally appointed leaders, with accountable responsibilities, who operate between senior leaders and teachers, and lead in order to positively impact teaching and student learning.

Description: School middle leaders are formally appointed leaders who operate between senior leaders and teachers, are accountable for their responsibilities, and lead in order to positively impact (directly and indirectly) teaching and student learning. They are impacted by, and benefit from, senior leadership support. They lead best within positive and trusting relationships. These relationships include those with students, parents, teachers, and senior leaders. As such they have a wide range of people that they influence and are influenced by. Middle leaders work to contribute to the professional agency of those they work with to influence them and to make choices that positively impact on teaching and learning.

Key characteristics: Five key characteristics of middle leadership were identified from the review (Table 4). See Appendix Table 1 for source references.

Table 4.

School middle leader characteristics.

Characteristics	Description
Formal position	Middle leaders are appointed to formal leadership positions that often include some form of remuneration.
Positionality	Middle leaders lead with and within a subculture between senior leaders and teachers and they require senior leadership support.
Teacher agency	Middle leaders actively work to contribute to, and shape, the professional agency of those they work with by influencing teachers and enabling them to make positive choices that impact (directly and indirectly) on teaching and learning.
Relational leading practices	Middle leaders lead and influence through trusting and collaborative relationships
Dual and mutual accountability	Middle leaders are dually accountable to their principal and their colleagues. Mutual accountability for professional learning between middle leader and colleagues ensures advancements in teaching and learning are a shared endeavour.

Research possibilities: Impact and professional development

Research into school middle leadership impact is important. The authors of the studies reviewed in this article often reported that middle leadership impact was most commonly indirect. None of the studies incorporated students as participants or included student data. We posit that without the consideration of student perceptions and learning data, caution is required in making claims about the significant impact of middle leadership practices on student learning. We recommend research that examines the relationship between MLs’ impact and teacher and student development.

Additionally, findings from this review suggest existing professional development offerings and research in middle leadership professional development are not yet sufficient to equip school MLs for the complexity of their roles. With an increase in focus on middle leadership development in countries such as Australia (Lipscombe et al., 2020a) and New Zealand (Bassett and Shaw, 2017), empirical studies to inform both the methodology and impacts of such courses are needed.

Conclusion

MLs plays an important role in school improvement. Results from this review highlight that school middle leadership is diverse, contextually driven, and important for advancing teaching and learning. A larger research base on middle leadership is needed to fill the gaps in the empirical research. This review has identified those gaps, specifically concerning impact and professional development, and it has provided an operational definition, description and set of characteristics of school middle leadership that may be supportive for future research, practice and policy work. We argue that the realisation of the full potential of middle leadership as impactful and supported is yet to be fully achieved.

Supplemental Material

Supplemental Material, sj-pdf-1-ema-10.1177_1741143220983328 - School middle leadership: A systematic review

Supplemental Material, sj-pdf-1-ema-10.1177_1741143220983328 for School middle leadership: A systematic review by Kylie Lipscombe, Sharon Tndall-Ford and Jodi Lamanna in Educational Management Administration & Leadership

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iDs

Kylie Lipscombe

Jodi Lamanna

Supplemental material

Supplemental material for this article is available online.

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