This study presents a primary trait analysis of a learner-centered, discrete mathematics course based on student-to-student instruction. The authors developed a scoring rubric for the primary traits: conceptual knowledge, procedural knowledge, application of understanding, and mathematical communication skills. Eleven students took an exam developed by the instructor, which was composed of seventeen performance-based problems without a single best answer, as a pre-test and post-test. Every student showed significant improvement in the four traits, with the least improvement in mathematical communication skills. The primary trait analysis shows that the course objectives were met and gave insights into how to improve the course. (Contains 6 figures and 5 tables.)