This study explores the design and evaluation of a pedagogical agent persona (PAP) to enhance project-based learning (PBL) in Ghanaian senior high schools. Using a design-based research approach, a multimodal human-like PAP was developed and tested with 15 students and two teachers. Data from interviews, observations and usability scales revealed high learner engagement and satisfaction, with the Learner Attenuated System Paced model scoring highest (SUS = 92). Findings suggest that a PAP can support instructional equity, autonomy, and engagement in large-class settings. The study offers practical insights for scalable learner-centred technology integration in under-resourced educational contexts.