*Article* **The Role of Commitment in an Extended Theory of Planned Behavior: Test of Its Mediating Effect with Partial Least Squares Structural Equation Modeling**

**Haoyi Huang and Eddie W. L. Cheng \***

Department of Social Sciences, The Education University of Hong Kong, Tai Po, Hong Kong, China; s1126279@s.eduhk.hk

**\*** Correspondence: wlcheng@eduhk.hk

**Abstract:** The theory of planned behavior (TPB) is popular for studying behavioral intentions. While the direct relationships between the three antecedents (i.e., attitudes toward the behavior, subjective norms, and perceived behavioral control) and intentions in the TPB have been extensively studied, the authors of this study hoped to draw attention to the variable "commitment". It is interesting to explore whether commitment mediates the relationship between the three antecedents and intentions. Furthermore, this study attempted to investigate if the TPB is appropriate for explaining students' intentions to learn sustainability. Like many other countries, sustainability has been widely integrated into primary and secondary education in China. However, if students are not interested in or feel that they are not capable of learning sustainability, they may be reluctant to do so. Therefore, this study aimed to examine an extended TPB model with a sample of 181 students from a public junior secondary school in China through factor-based partial least squares structural equation modeling. The results showed that the model could explain the intention to learn sustainability. Specifically, this research found that commitment mediated the relationships of attitudes toward learning sustainability, subjective norms, and perceived behavioral control to the behavioral intention.

**Keywords:** theory of planned behavior; commitment; PLS-SEM; geography education; intention

**MSC:** 62H15
