Growing evidence suggests that traditional grading systems are, at best, imperfect measures of student learning and, at worst, do harm to student motivation, confidence, persistence in the field, and student-faculty relationships. Some studies suggest this is exacerbated by other factors that impact the experiences of students from underrepresented groups in STEM and lower performing students, resulting in increased negative impacts for these students. As instructors increasingly adopt alternative grading systems such as specifications grading, standards-based grading, and ungrading in an attempt to mitigate these negative effects, we have an obligation to understand the impacts of these alternative systems on students. This study evaluates the impacts of a specifications grading system on student learning, engagement, and motivation in a large introductory physical geology course at an R1, private university, testing a hypothesis of improved student motivation. Student learning, indicated by grades and performance on learning objective-aligned exam questions, and student engagement, measured through time and frequency of engagement with online course materials, are analyzed for the same course in semesters where traditional grading was used and compared with alternatively graded semesters. Impacts on key aspects of motivation are assessed using the Science Motivation Questionnaire II (Glynn et al., 2011) in the context of social cognitive theory, considering measures of intrinsic motivation, self-determination, self-efficacy, and extrinsic motivation. Student survey responses were collected at three points during the semester of the alternatively graded course and resulting measures of motivation parameters are evaluated in the context of self-identified student major, gender, race, and first-generation college students.