The purpose of this study was to design, implement, and evaluate a course according to a STEM education approach for pre-service science teachers. The study was conducted in three phases according to an educational design research method: preliminary research, development or prototyping, and assessment (Plomp & Nieveen, 2013). The STEM education pre-knowledge form, STEM lesson plans, the STEM lesson plan evaluation form, STEM self-evaluation, and peer-evaluation forms, and a semi-structured face-to-face interview form were used as qualitative data collection tools. Data were analyzed by methods of content analysis. The results suggest that pre-service science teachers need education in the dimensions of the theoretical structure of STEM education, STEM disciplines and integration, 21st-century skills, sample STEM activities, current science curriculum, STEM learning/teaching methods and techniques, measurement and assessment for STEM education, collaboration with peers, and planning-implementing a lesson according to STEM education. The findings showed that the STEM course design developed through this study was seen to be effective in responding pre-service teachers' needs. In STEM course design, six activities were prepared in the context of designing a 21st-century house and designing a vehicle according to the trans-disciplinary model and hands on minds on method. According to the relevant literature, the findings were discussed and future studies should provide collaboration with pre-service teachers, students, and in-service teachers. Future studies should also focus on developing the knowledge and skills of pre-service teachers about engineering and technology discipline and show how to integrate these disciplines into their real-life problems.