Teacher education programmes struggle to attract, develop, and retain potential teachers in Science and Mathematics. The development of both academic and non-academic attributes (e.g. adaptability, empathy) during a programme can influence not only retention but the profession-readiness of graduates. This is especially important in underserved schools where high attrition rates are more likely with Science and Mathematics teachers in their first few years of teaching. Yet most programmes lack intentional opportunities for non-academic development. Using a qualitative case study approach with an established think-aloud protocol, nine pre-service teachers (Science or Mathematics) were presented with situational judgment test items. A three-step analytical strategy revealed participants' reasoning with a range of motivational beliefs and values. Results point to four broad reasoning profiles (solution, consequence, student, and value-focused). By exploring the implicit and explicit beliefs and values that contribute to prospective teachers' reasoning processes, we offer implications for professional development and future research.