The transition from high school to university is an important phase in the educational journey of many students. This stage not only serves as an access for university enrollment but also equips students to handle the challenges at university. This study investigates the influence of prior academic performance, as measured by A-level grades, on university cumulative grade point average (CGPA) and persistence to graduation while also exploring how academic engagement mediates this relationship. Using a post-positivist lens, sequential explanatory mixed-methods research design was applied, with emphasis on quantitative analysis of data and followed up by a qualitative analysis of data to explain the statistically significant results. The targeted population included final-year students from four participating schools at Makerere University, totaling 1,273 students. The study utilized a simple random sampling technique, allowing all final-year students from the four schools an equal chance to participate, which caused the realization of the final sample of 754. SPSS V26 was utilized to conduct correlation and regression analyses to explore the relationships and predictive power of A-level grades on college CGPA and persistence. Additionally, a mediation analysis was performed to assess the indirect effect of academic engagement on the link between A-level performance and university CGPA. The correlation findings indicated that A-level grades have a significant impact on students' cumulative grade point average (CGPA) but do not significantly affect their persistence in university. Consistent with prior research, academic involvement was found to significantly influence both CGPA and persistence. Additionally, the analysis showed no significant correlation between A-level grades and academic engagement, as well as an insignificant indirect effect of academic engagement on the relationship between A-level points and CGPA. To gain further insight into these statistically significant results, qualitative data collection and analysis were conducted using a purposive sampling method. Fourteen students voluntarily shared their experiences to elucidate the relationships, leading to the emergence of several key themes. For example, strong study skills, motivation, and intellectual ability were identified as reasons why students with higher A-level grades tend to achieve higher CGPA in university. Additionally, a solid grasp of concepts and increased confidence were highlighted as factors explaining why academic engagement positively predicts both CGPA and graduation persistence. Based on the findings, the study concluded that both A-level grades and academic engagement were critical factors toward university success. Therefore, the study recommended that Makerere University and other higher education institutions uphold the current A-Level cut-off requirements for admission into different university programs as may be deemed so. Besides, faculty members should prioritize creating an engaging learning environment that promotes interactive and meaningful experiences, utilizing methods such as collaborative learning sessions, projects, peer-to-peer interactions, and class presentations. By fostering this culture, students are more likely to excel academically and persist in their studies until graduation, as they will perceive their learning as both meaningful and rewarding.
