Mediating Role of Teacher Empowerment on the Relationship between Instructional Leadership and School Effectiveness

This research work examines the mediating role of teacher empowerment on the relationship between instructional leadership and school effectiveness. The study employed a correlational design. The population of the study comprised of 2361 teachers serving in 158 secondary schools across Zamfara State. A total number of 330 teachers were sampled using Cochran’s formula of determining sample size. Data was collected through field survey approach. The data was analysed using both descriptive and inferential (Partial Least Square [PLS] path modelling) statistics. Results from the study revealed that; there is a significant relationship between instructional leadership, teacher empowerment and school effectiveness. It was also found that, teachers’ empowerment mediates the relationship between instructional leadership and school effectiveness with a direct significant positive correlation with statistical value (Beta=0.199, t=7.187, p< 0.05). The study therefore recommends that; school principals should adopt instructional leadership practice with teacher empowerment for the attainment of an effective school system.

into functional members of the society by making provision of control to them over their behaviours and personality traits. In order to assume leadership roles, it is essential for the individuals to generate awareness and augment their competencies, so they can perform their job duties in a well-organized manner within the educational institutions (Tng, 2009;Kapur, 2021). According to Zamfara State Government (2017), instructional leadership is essential for the attainment of desired progressive development, implementation, and evaluation of outcomes from the establishing goals of the school. Instructional leadership focuses on strengthening capacity for planning and coordination. It also put in place periodic review and evaluation mechanisms to track progress. It also focuses on improving coordination between the various agencies in the Education Sector as well as other agencies. Teachers cannot effectively and efficiently execute the above duties without themselves being properly and adequately empowered, provided for and monitored (Ofojebe et al., 2016). Hence, teachers are the critical elements in any educational system. They are the public face of education, and their direct actions influence school characteristics such as curriculum implementation, execution of the established policies on education, students' academic achievements, effective school management, and maintenance of the schools' infrastructural facilities, among others (Crosswell, 2006). Therefore, teacher empowerment has become an integral part of school reform as teachers become more involved in school improvement initiatives (Sharp, 2009). Seemingly, teacher empowerment has profound implications for the lives of teachers, for students, for administrators, for schools, and for society as a whole. The empowerment of teachers provides them with the long denied opportunities to apply their energies, knowledge, and expertise to the achievement of school goals through the development of their leadership competencies (Rallis, 1988). Cunnningham & Gresso (1993), contended that empowerment encourages all educators to their fullest potential. The demands placed on educationists as leaders of schools are numerous. Marzano, et al., (2005), believed that leadership is linked to a variety of effective educational practices that address students learning opportunities, teacher effectiveness, organization of curriculum and instruction, school climate, and the establishment of the mission and vision. Effective leadership is essential to the participatory decision making necessary for successful school reform (Sharp, 2009). Instructional leadership and its direct or indirect effects on student achievement has been a popular area of study by researchers in the field of educational leadership (Leithwood & Jantizi, 2005). According to McEwan (1998), most principals do not put instructional leadership as their primary responsibility due to lack of skills and training, lack of support from the superiors and the community as well as lack of vision, commitment and enthusiasm. There is quite an array of studies that substantiate the failure of principals in performing their role as instructional leaders (Sim, 2011). For instance, Croft's study which (1968) examined the differences between the ideal role and the actual role of principals revealed that principals never see them teach during class time, and that the principals were extremely rare in providing comments or suggestions related to teaching. Teacher empowerment has become an integral part of school reform as teachers become more involved in school effectiveness/improvement research investigations and educational policies. However, principals' leadership style and responsibilities have caused some teachers to feel disempowered in a school environment (Sharp, 2009). In spite of the significance of teacher empowerment towards the realisation of viable instructional leadership in education and school effectiveness, prior researches were critically analysed and thus found to have revealed that, there have been unsolicited factors affecting the process of teacher empowerment. Hallinger & Murphy (1987); Ponnusamy (2010), reported in their study that one of the main obstacles that hinder school heads from exercising strong instructional leadership is the lack of knowledge about the curriculum and instruction. Thus, they need to have the best leadership and management practices and equip themselves with essential professional skills so as to face the challenges in their organization. This is because, school leaders have long believed that instructional leadership which consists of supervision, staff development and curriculum development facilitates schools' effectiveness and improvement (Blase & Blase, 2004). According to Zamfara State Government: Report of the Zamfara State Secondary Education Assessment Committee ZSSEAC (2014), there is lack of qualified teachers, poor teachers' welfare, poor record keeping and maintenance, most schools do not have inventory register, account books, reward and punishment books, National Policy on Education and National Curriculum (Even where available, such records are not updated as regularly as they should be). Appointment of unsuitable persons as educational leaders (Like, Principals and Vice Principals). Some educational administrators are too junior in terms of rank, qualification and experience to provide appropriate leadership in the schools they lead. These factors however rendered Zamfara as educational disadvantaged State in the country (Zamfara State Government: Education Sector Medium Term Sector Strategy, 2017). Furthermore, there is a theoretical gap in literature as regards to the mediating effect of teacher empowerment between instructional leadership and school effectiveness. Most of the related existing researches focused on the direct relationship between instructional leadership and school effectiveness. Therefore, the two main objectives of this study are: Firstly, , secondly and then thirdly

Research Objectives
1. To determine the relationship between instructional leadership and school effectiveness. 2. To determine the relationship between teacher empowerment and school effectiveness. 3. To determine the mediating effect of teacher empowerment between instructional leadership and school effectiveness.

Literature Review School Effectiveness
It is too complicated to define school effectiveness because too many factors influence the effectiveness of the school (Zamir, 2020). The conceptualization of effective schools varies among researchers. Some researchers have concentrated on academic outcome of the students while others concentrated in attitudes and conduct of the students (Dodson, 2005). However, Edmonds (1986); Dahiru et al (2017), blended the researches and came up with some factors associated with effective schools named as five-factor model of school effectiveness. The factors are thus, strong administrative leadership, basic skill acquisition, high expectations for student success, a safe and orderly environment and frequent assessing of student achievement (Horner, et al., 2009). Similarly, Lezotte and Jacoby (1991), in conducting school effectiveness research identified seven correlates of effective schools which emanated from the original correlates shared by Edmonds (1986) cited by Dahiru et al., (2017), added two variables through empirical research findings. The correlates are: strong instructional leadership, clear and focused vision and mission, safe and orderly school environment, high expectations for success, continuous assessment of student achievement, opportunity to learn and time on task and positive home-school relations. Therefore, school effectiveness is a very much wider concept. School effectiveness refers to aspects of teaching, learning, motivation and community involvement. Many of the factors which refer to the study of school effectiveness. Therefore, it is maintained that a school is judged as effective provided that the result of its activities meets up with its goals (Mielcarek, et al., 2005). Some prior studies on educational administration revealed that, school effectiveness refers to school improvement efforts and measurement of student achievement. However, other researchers argued this statement and explain that the school's effectiveness was more focused on the behavior in the classroom, student participation and value of learning (Rutter, 1983;Abdullah et al., 2016). A critical analysis of the reviewed literature on school effectiveness have shown that several definitions of the concept provide divergent views of what an effective school is or what constitutes school effectiveness this diverse views lead to the conclusion that while all reviews assume that effective schools can be differentiated from ineffective ones there is no consensus yet on just what constitutes an effective school (Dahiru, et al., 2017).

Instructional Leadership
According to Tice (1992); Kwinda (2002), Instructional Leadership means enhancement of staff abilities. It may mean educators helping educators and includes involvement of staff members. An instructional leader understands and makes decisions which improve instruction and curriculum. Furthermore, Westhuizen (1998), further asserted that instructional leadership is the ability of the school principal to carry out developmental supervision and provide for the curriculum in the school. Instructional leadership is defined as leadership that puts teaching and learning in the school as a priority in order to improve students' learning (Botha, 2011). Instructional leadership encompasses those actions that the principal takes or delegates to others, to promote students learning (Dinie, 2017). It comprises the following tasks: defining the purpose of schooling; setting school wide goals; providing the resources needed for learning to occur; supervising and evaluating teachers; coordinating staff development programmes; and creating collegial relationships with and among teachers (Dimmock & Wildy, 1993). Instructional Leadership can be seen as the actions school heads (Headmasters/Principals) take or delegate to others in order to improve students' learning. Instructional Leadership encourages educational achievement by making the instructional quality in the school organization as the top priority and brings the stated vision to realization (e-lead, 2010). Instructional leaders align the school's academic mission with strategy and action. They are focused not only on leading, but also on managing. According to Wing (2013), the instructional leaders in a school environment should create a shared sense of purpose in the school, nurture continuous improvement through school development planning, develop a school culture aimed at innovation and the improvement of teaching and learning, coordinate the curriculum and monitor learner outcomes, shape the reward structure of the school, organize and monitor a wide range of activities and be a visible presence in the school. Instructional leadership plays a role in the development of teacher performance as well as planning, coordinating and evaluating teaching and learning activities in schools (Malaysian Ministry of Education, 2013; cited by Jamalullail, et al., 2020) noted that in Nigeria, most of the success or failures in secondary schools' administration or other institutions depends largely on the influence of the leaders on their subordinates. The success or failure of every school principal depends mostly on the principal's influence on the teachers through his leadership style. H1: There is a significant relationship between instructional leadership, and school effectiveness.

Teacher Empowerment
Teacher empowerment has become increasingly visible within current trends related to educational best practices. The empowerment of employees serves as a significant factor in the success of the schools, businesses, or other organizations in which people are working toward a common goal. Teacher empowerment and teachers' sense of empowerment represent important variables in comprehensive school improvement efforts of today's effective school's movement (Sharp, 2009). The concept of teacher empowerment has been regarded by various researchers as stimulating collegiality, recognizing the influence of teachers on student achievement and providing excellent skilled learning (Zembylas & Papanastasiou, 2005). Decision making regarding teaching and learning is solely the duty of teachers, therefore it is paramount to study the circumstances that will guarantee the effectiveness of teachers are (Kelly, 2012). According to Angelle et al (2011), student's achievement is central in teacher empowerment.  stated that school improvement is dependent upon provision of opportunities for teachers to partake in the process of decision making in key areas within a school. They defined teacher empowerment is defined as a process whereby members grow the capability to take responsibility of their own growth, determine their own problems and develop the confidence that they pose the skills and knowledge to tackle a situation and improve upon it . Characteristics of effective schools are indispensable in the attainment of teacher empowerment. They offer ample opportunity and self-confidence to teachers to become innovative. It encompasses having self-confidence on teachers about their trust worthiness, reliability and their capability in executing their responsibilities autonomously, without any type of supervision. It boosts teacher participation in the decision making process (Knapp, Copland, & Talbert, 2003). H2: There is a significant relationship between teacher empowerment and school effectiveness. H3: Teacher empowerment mediates in the relationship between instructional leadership and school effectiveness.

Methodology Participants
The population of the study consisted of all the serving teachers in the public secondary schools in Zamfara state, Nigeria. According to the records there are 2361 teachers serving in 158 secondary schools across the state. Cochran's formula (2007) was used to determine the sample size. Therefore, the total sample distributed is 330 to teachers all over the state, out of which 266 (81%) were returned. The choice of the participants was made through a multistage random sampling due to the reason that all the teachers possess the same characteristics. According to the results of the descriptive statistics, among the participants, 63% are male while 37% are female. In terms of educational qualification, only 1.1% of the respondents holds a master degree, 72.2% were holders of Bachelor of education degrees and 26.7% were having Nigerian Certificate in Education.

Instrumentation
Three instruments were adopted to measure the variables of the research. For school effectiveness, Lezzote and Snyder (2011) five Likert type scale instrument ranging from (Strongly disagree, disagree, slightly agree, Agree and strongly agree) with 21 items was adopted. Similarly, instructional leadership questionnaire developed by Akram (2017) was adopted to measure instructional leadership practice. It is a five Likert type scale consisting of 15 items. Furthermore, in order to measure teacher empowerment,  instrument titled school participants' empowerment scale with 13 Items was adopted.

Data Analysis
The study applied smart PLS version 3.2.7 to present the main results of measurement and structural model. The measurement model was used to test the goodness of the measuring instrument indicator reliability, internal consistent reliability, convergent reliability and, discriminant validity analysis. while, the structural model was tested to verify the hypotheses followed by determination of effect size, determination of model predictive relevance and collinearity statistics.

Assessment of Measurement Model
Before the main analysis, a number of assumptions of normality, multicolinearity, and linearity were checked (Hair et al., 2010). Also common method bias was assessed with Harma's single factor test. After meeting up with all the assumptions, Partial Least Square (PLS) path modelling using smart PLS 2.0 M3 software (Ringle, et al., 2012). The reliability was assessed using composite reliability (CR) while validity was assessed using convergent validity average variance extracted (AVE) and discriminant validity via Fornel-Lacker Criterion and predictors outer loadings.  figure 2 shows that the CR value in this study is between 0.941 and 0.919 which is an indication of adequate internal consistency (Nunally & Bernstein, 1994). Furthermore, all CR values have exceeded the minimum threshold value of 0.70 (Hair, et al., 2013) The convergent validity as shown in table 2 above has met with the minimum requirements of 0.5 and this indicates that the convergent validity is met. Lastly, constructs and discriminant validity were examined through the examination of cross loadings and Fornel and Lcker (1981) criterion (Hair, et al., 2013). Table 3 above indicates that separately constructs AVE square root is greater than its correlation with all other constructs. Moreover, no indicator loaded greater on any distinct construct (Hair, et al., 2013).

Structural Model
The assessment of the structural model is the next stage after establishing the measurement model and the basic recommended criteria are conducted and satisfied the required result. This study assesses the structural model which involved evaluating of the coefficient of determination (R 2 value), the model's predictive capabilities determination of the latent variables' path coefficients, individual independent variables, and the effect size (Anderson, J & Gerbing, D, 1988;Barclay, Thompson, & Higgins, 1995;Hair, et al., 2013;Hair, et al., 2010).

Assessment of the Structural Model Direct Relationship
The structural model assessment was conducted using applied bootstrapping method with 5000 bootstrap samples to measure the significance of the path coefficients for the twelve hypotheses (Hair, et al., 2014;Hair, et al., 2012b;Hair, et al., 2016;Henseler, et al., 2009). The path coefficients consist standardized values approximately between -1 and +1, the significant of coefficient depends on its standard error that is found by means of bootstrapping. Similarly, bootstrap confidence interval was also employed in this study in testing whether a path coefficient is significantly different from zero. "This offers information on the stability of the estimated coefficient by offering a range of plausible population values for the parameter dependent on the variation in the sample size and the data. the bootstrap confidence interval is based on standard errors derived from bootstrapping and specifies the range into which the true population parameter fall assuming a certain level of confidence (e.g., 95%). If a confidence interval for an estimated path coefficient does not include zero, the hypothesis that the path equals zero is rejected, and we assume a significant effect. While research has brought forward a range of different bootstrap confidence intervals, we recommend using the BCa approach in line with prior research" (Hair, Sarstedt, Ringle, & Gudergan, 2017). Figure 3 and Table 4 shows estimation for the direct relationship that comprises mediating variables. The structural construct of study.  Table 4, and figure 3 revealed a positive relationship between instructional leadership and school effectiveness (Beta=0.603, t=15.379, p< 0.05, indicating that hypothesis 1 is supported. Hypothesis 2 predicts that teacher empowerment is positively related to school effectiveness. Table 4 and Figure 3indicates that (Beta=0.326, t= 15.220, p<0.05, supporting hypothesis 2.

Testing Mediating Effect
To test for the mediation effect of teacher empowerment, all the mediation procedures were followed and it was found that all the conditions of mediation as recommended by Baron and Kenny, (1986) were satisfied. Therefore, hypothesis 3 predicted that teacher empowerment would mediate between instructional leadership and school effectiveness. As shown in Table  4 above, there is an evidence of indirect effect of instructional leadership on school effectiveness through teacher empowerment. Therefore, the study proves that teacher empowerment mediates between instructional leadership and school effectiveness, (Beta=0.199,t=7.187,p< 0.05). This finding supports hypothesis 3.

Discussions
Results of this study found that, there is a significant relationship between instructional leadership and school effectiveness with statistical value (Beta=0.603, t=15.379, p<0.05). In other words, if the mean score of instructional leadership increases, the mean score of school effectiveness will be highly increased. This finding is in agreement with the findings of Dahiru (2017) who found that there is a positive relationship between instructional leadership and school effectiveness. Similarly, Xaba & Malindi (2010) reported that practice of instructional leadership is significantly related to the realization of school effectiveness as it addresses obstacles that include shortage of resources, high population of students among others. Thus, principal's that practice instructional leadership are most likely to have effective schools. Also, results from this study have indicated that teacher empowerment is positively related to school effectiveness with statistical value of (Beta=0.326, t=15.220, p<0.05). In other words, the more the teachers are empowered the higher the school will be effective. This finding is in harmony with some prior research works, like Dahiru (2017) who discovered in his study that there is a significant relationship between teacher empowerment and school effectiveness. According to him, if teachers are given autonomy to decide on their jobs, have an impact on school decisions and provided with trainings on how to conduct their jobs, then the school will be more effective. Furthermore, Maniam et al (2017) found in their study that, there is a significant relationship between teachers' empowerment and school effectiveness indicating that one of the crucial factors that affect school effectiveness is teachers' empowerment.
On the other hand, the current research established that teacher empowerment mediates on the relationship between instructional leadership and school effectiveness. This was determined through the statistical value (Beta=0.199, t=7.187, p< 0.05) indicating that. Thus, the independent variable (Instructional leadership), the mediating variable (Teacher empowerment) and the dependent variable (School effectiveness) could be seen as interwoven together. This finding is in agreement with that of Maniam et al (2017) who discovered in his study that, teacher empowerment significantly mediates instructional leadership and school effectiveness. Javaria et al (2020) also found in their study that, teachers' empowerment mediates the relationship between authentic instructional leadership and school effectiveness in Pakistan. According to them, there is a direct positive significant effect of teachers' empowerment on instructional leadership on teachers' job performance which would lead towards the actualisation of school effectiveness.

Conclusion
This study was conducted to examine the mediating effect of teacher empowerment in the relationship between instructional leadership and school effectiveness among the secondary school of Zamfara State-Nigeria. Partial Least Square (PLS) path modelling using smart PLS 2.0 software was employed in order to determine the relationship between the variables under study as well as the mediating effect of the mediating variable. Based on Partial Least Square (PLS) path model of the study was found to fit with the data. The results obtained in the study have shown a significant relationship between instructional leadership, teacher empowerment and school effectiveness. Furthermore, it was found that, teacher empowerment mediates in the relationship between instructional leadership and school effectiveness with a direct significant positive correlation. The implications of the findings highlight the need for school principals to apply instructional leadership practice for the attainment of an effective school system. The ministry of education and other relevant stakeholders also have a task of designing and formulating policies and programs that would enable the application of instructional leadership with teacher empowerment in the day-to-day administration of their schools for the realization of an affective school system. Although, this study provides a better understanding of the mediating effect of teacher empowerment between instructional leadership and school effectiveness it was only focused on secondary schools in Zamfara State, in the north-western geo-political zone, Nigeria. Therefore, the findings cannot be generalised to Nigeria as a whole.