This study investigates the thematic structure of collaborative project work by analyzing co-occurrence patterns of thematic tags and their correlations with sentiment scores under the principles of Design Thinking. The research involved twenty-five foundation-level students from physics, management, and energy programs in a 10-week intervention consisting of hands-on workshops, group projects, and reflective activities. Students engaged in all five stages of the DT process—empathize, define, ideate, prototype, and test—by identifying real-world problems, developing solutions, and constructing physical prototypes. Qualitative data from student self-reflection reports were analyzed using thematic analysis and Natural Language Processing (NLP). Weekly sessions were conducted to guide iterative development and collaborative thinking. Qualitative data were collected through students’ self-reflection reports and analyzed using thematic analysis and Natural Language Processing (NLP) techniques. Using a qualitative dataset coded for themes such as teamwork, leadership, prototyping, communication, support, and learning, a co-occurrence matrix and a sentiment correlation matrix were generated. Overall, the analysis illustrates a clear interplay between cognitive, social, and emotional factors in students’ project-based learning experiences. Prototyping emerged as a collective process that integrated creative ideation and teamwork, while positive emotions were predominantly driven by supportive and communicative interactions. These findings reinforce the notion that effective learning in collaborative design settings relies not only on technical competence but also on empathetic and interactive engagement. This research contributes to the limited body of literature on DT at the tertiary education level in Malaysia, where its application is largely confined to business and creative arts programs. The outcomes highlight the relevance of DT in STEM and interdisciplinary foundation education, supporting national education priorities under the Malaysia Education Blueprint.