["European Journal of Education, Volume 61, Issue 2, June 2026. ", "\nABSTRACT\nTreating teachers as mere tools or instruments, denying them of their humanity for the school's goals, causes them to teach in dehumanizing times. Recent research indicates that organizational dehumanization may have a significant impact on an individual's self‐efficacy and work behaviour. However, the causal relationship between organizational dehumanization and self‐esteem, self‐efficacy, and demotivating teaching style remains unclear in this literature. Utilizing job demand‐resources theory, we examine the mediating role of self‐esteem and the moderating role of perceived coworker support in organizational dehumanization and teacher self‐efficacy and demotivating teaching style relationships. Data were collected from early childhood (N = 307) and primary (N = 664) teachers for study 1 (an experimental study) and study 2 (a three‐wave study), respectively. Overall, the combined results of experimental and three‐wave studies provide strong evidence that experiencing dehumanizing treatment from the school leads teachers to internalize negative self‐evaluation, leading to low self‐esteem, which subsequently reduces teacher self‐efficacy but increases demotivating teaching style adoption. And this detrimental effect is less critical among teachers with high perceived coworker support. This study sheds light on dehumanization in the school setting by suggesting practical implications to reduce dehumanizing practices and highlighting the importance of perceived coworker support among teachers in classroom practices.\n"]