Undergraduate retention in STEM majors has been a longstanding concern with educators. By virtue of the curriculum, mathematics is more prominent in some STEM majors such as Physical science, Computer science, Engineering, and Chemistry. First, using a metaanalytic approach, the role of SAT math score, first college math course, and first college math grade in predicting STEM undergraduate retention was investigated. Next, a qualitative narrative inquiry was conducted to understand the role of mathematics in freshmen year engineering in the broader context of academic and non-academic factors influencing retention. Finally, given that facing academic difficulties was common among engineering freshmen, students' reactions to negative feedback was observed in a lab setting. The role of individual personality traits in reacting to academic feedback was investigated. The results suggested that first year mathematics course-taking experiences influenced student retention. Specifically, students who received lower than a C grade in first semester math were highly likely to drop out of their STEM majors. Participants considered mathematics, chemistry and coding as the most challenging courses during freshmen year. Being academically underprepared for these courses was a drawback for freshmen engineering students. While better high school preparation helped students perform, psychological factors such as motivation and personality were important factors in overcoming academic challenges. The personality trait closely related to academic performance, conscientiousness, was not predictive of effectively responding to negative feedback. However, other personality traits such as emotional stability, and openness, played an important role in navigating academic challenges. Understanding students' reactions to academic challenges is a vastly under explored area of research, especially in the context of undergraduate STEM majors.