This study is the first to explore how skill and effort drive student achievement using a framework developed by Duckworth, Eichstaedt, and Unger (2015). A statistically significant achievement difference, as measured by Comprehensive Business Exam score during the last semester in college, was identified when students were separated by standard deviations from the ACT score mean, a measure of college entry-level skill. Implications for assurance of learning assessment are presented and possible avenues of remediation are considered.