Student characteristics and academic motivation in academic achievement: The roles of school engagement and teacher justice

The purpose of this study is to examine the mediating role of school engagement and the moderating role of teacher justice in the relationship between motivation and academic achievement, and to develop the Teacher Justice Scale (TJS). The study used a predictive correlational design. In addition, an exploratory sequential mixed design was used to develop the TJS. The study group consisted of 598 high school students attending the 9th, 10th, 11th, and 12th grades in Ankara province and its districts in the 2023-2024 academic year, selected by convenience sampling. In addition, six focus group interviews, each consisting of eight high school students, were conducted during the development process of TJS. A semi-structured interview form was used. Validity and reliability analyses of the items created in line with the interviews were conducted in two separate study groups using exploratory structural equation modelling and confirmatory factor analysis. Cronbach's alpha coefficients were above the cutoff score. Data were collected using a personal information form, a school engagement scale, an academic motivation scale, and a perceived social support scale. The findings showed that academic motivation predicted school engagement, and academic achievement and school engagement positively and statistically significantly predicted academic achievement. In addition, school engagement fully mediated the relationship between academic motivation and achievement, and the indirect effect increased linearly at low, medium, and high levels of teacher justice. The findings are discussed in the context of self-determination theory and related literature. Recommendations were made for policy makers, researchers, practitioners and teachers.