This assessment study examined one potential instructional method for improving student learning in Calculus for majors, flipped learning, in comparison with traditional lecture-based instruction. Results suggest that participation in flipped learning substantially improved growth in achievement over the semester, final exam grades, and final course grades. In contrast, there was no difference between the two groups in terms of students' beliefs about learning mathematics. Additionally presented is a review of the changes made from the first year to the second year of implementing flipped learning, and how these changes are believed to have assisted with the increased impact on student learning.