--- - |2+ Abstract Objective In the present research, we examined the effect of getting a new teacher on consistency in students’ personality measures, including trait and social cognitive constructs. Method To test the effect of this kind of situational transition, we analyzed two large longitudinal samples (N = 5,628; N = 2,458) with quasi‐experimental study designs. We used two consistency measures (i.e., rank‐order clations and changes in variance over time) to compare students who got a new teacher with students who kept the same teacher. Results Multiple‐group latent variable analyses showed no differences in the rank‐order correlations for the math‐related social cognitive constructs of interest, effort, self‐concept, self‐regulation, anxiety, and the Big Five personality traits. Significantly lower rank‐order correlations were found for some of the German‐ and English‐related social cognitive constructs (i.e., effort measures) for the group of students who got a new teacher. Regarding the changes in variance (over time), we found no systematic differences between groups in both studies. Conclusions We found partial support for the idea that social cognitive variables are more susceptible to environmental changes (i.e., getting a new teacher) than the Big Five personality traits are. - Journal of Personality, EarlyView.