In spring 2020, three partnering academic programs of the "tri-alliance"—occupational therapy, physical therapy, and speech-language pathology—immediately transitioned from hybrid interprofessional education(IPE) to uniprofessional, online learning experiences due to the COVID-19 pandemic. This transition presented opportunity to compare attitude changes and understand student perceptions about interprofessionalcollaboration between two tri-alliance student groups: Case 2018, N = 119 and Case 2020, N = 95. By incorporating the Bioecological Theory of Human Development (BTHD) and the Ecology of Human Performance (EHP), a comparative mixed methods case study merged quantitative results from a natural experiment and qualitative findings from a case study to learn about ecological factors within IPE and their effects on studentlearning. A modified version of the Interprofessional Attitude Scale provided quantitative pre- and posttest results. Narrative responses to reflection questions provided insight into the students' perceptions. These results were analyzed separately and then merged together for both Cases. The outcomes between Cases diverged and provided evidence that attitude changes and perceptions from Case 2018 were significantly more positive than from Case 2020. Based on the BTHD, ecological factors related to multiple levels of context influenced student engagement in their full IPE-based experiences, which ultimately affected development. However, after sample size modifications, the outcomes were similar and appeared to be more influenced by the person factors than context, in alignment EHP constructs. These outcomes provided evidence that ecological factors affect student engagement in and learning from IPE, and more attention is needed about student factors and teaching/learning contexts.