This study investigated the impact of a structured growth mindset intervention on the academic performance and psychological profiles of low-achieving students at Kampala International University (KIU). A quasi-experimental, pretest-posttest control group design was employed, with 200 academically at-risk students (GPA < 2.0) randomly assigned to either an experimental group that received a four-week growth mindset workshop or a control group that participated in a placebo session. Data on Grade Point Average (GPA) and psychological metrics (mindset and resilience) were collected pre- and post-intervention and analyzed using multiple linear regression in SPSS and STATA. The results demonstrated a statistically significant positive effect of the intervention. The regression model predicting end-of-semester GPA showed that participants in the experimental group achieved GPAs that were 0.38 points higher on average than the control group (B = 0.38, p < .001), even after controlling for prior academic performance. Furthermore, the intervention significantly improved students' psychological profiles, with the experimental group showing markedly higher levels of academic resilience and stronger growth mindset beliefs. A key finding was a significant dosage effect, wherein the degree of change in a student's mindset score was a direct positive predictor of both their increased resilience (B = 2.95, p = .003) and their improvement in GPA (B = 0.11, p < .001). The study established a clear causal pathway whereby the workshop altered maladaptive beliefs about intelligence, which in turn fostered greater perseverance and directly led to improved academic performance. It is recommended that KIU institutionalize these findings by integrating a mandatory growth mindset module into firstyear orientation, implementing targeted workshop series for at-risk students, and providing comprehensive growth mindset pedagogy training for academic staff. These actions are essential for translating this evidence-based intervention into sustainable institutional practice to improve student retention and success.