This study investigated the statistical significance of student trust next to the well-tested constructs of personality and motivation to determine whether trust is a significant predictor of course achievement in college math courses. Participants were 175 students who were taking undergraduate math courses in an urban public university. The Mini-Markers (Saucier, 1994), an adapted Student Trust Survey (Barnes, Adams & Forsyth, 2004, April), and the Motivated Strategies for Learning Questionnaire (Pintrich, Smith, Garcia & McKeachie, 1991) were used to measure students' Big-Five personality factors, trust in their math instructor, and motivational beliefs and strategies for their learning and performance in one of the math courses they were taking during Spring 2009. Students reported their semester in college, gender and ethnicity; their final math grades and math class size information were collected from the university at the end of the semester; and their math course group was determined based on the categorization made by the university's math department. The data were analyzed using bivariate correlations, independent samples "t"-tests, and hierarchical multiple regression models. The Conscientiousness factor correlated significantly with students' final math grades, explaining 6% unique variance in students' grades. Students' trust in their math instructor also correlated significantly with their final math grades, contributing another 6% unique variance to the prediction of students' grades. Students' task value, self-efficacy beliefs, test anxiety, and effort regulation were all significantly correlated with their final math grades, and when these were added in the final prediction model, the significant effects of the Conscientiousness factor and student trust on students' grades became non-significant. This showed that students' motivated strategies for learning completely mediated the relationship between students' Conscientiousness factor, trust, and their final math grades. The final prediction model explained 48% of the variance in students' grades, in which the significant predictors after controlling for students' gender, math course group, and math class size were students' self-efficacy beliefs, test anxiety, and effort regulation in their math course. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]