This study investigates the validity and instructional value of a rubric developed to evaluate the quality of online courses offered at a midsized public university. This rubric is adapted from an online course quality rubric widely used in higher education, the Quality Matters rubric. We first examine the reliability and preliminary construct validity of the rubric using quality ratings for 202 online courses and eliminate 12 problematic items. We then examine the instructional value of the rubric by investigating causal relationships between: (a) course quality scores, (b) online interactions between students, instructors, and content, and (c) student course performance (course passing rates). A path analysis model, using data from 121 online courses enrolling 5,240 students, show that only rubric items related to "learner engagement and interaction" have a significant and positive effect on online interactions, while only student-content interaction significantly and positively influence course passing rates.