Although it has emerged as a factor in performance effectiveness in both working adults and college students, hardiness has also been shown to be related to other factors that may well also be related to performance effectiveness. Consequently, attempts need to be made to determine whether the relationship to performance of hardiness is anything more than a mere reflection of its relationship to these other factors. This approach, which was begun in the comparison of the relative role of hardiness, optimism, and religiosity in performance effectiveness, is continued in the present study. Specifically, the relationship to grade point average of hardiness and related variables is compared. The related variables involve attitudes toward school and a sense of life’s meaning and one’s well-being. The results confirm the expectation that hardiness is a central factor in school performance.