For several decades there has been a broad consensus on the need to promote scientific literacy and, ultimately, to promote the full development of student competency from an early age. However, many of the results recorded in the educational field are not very encouraging. Although interdisciplinarity has a more extensive trajectory, the continuous questioning of traditional teaching methods, due to their inefficiency, has given rise to the emergence of educational approaches that integrate the teaching of diverse scientific disciplines in a more contextualized, coherent, and comprehensive manner. The body of empirical research on the application of these approaches has grown, while leaving behind some essential theoretical questions. In the present work, a theoretical framework is proposed for integrated science, technology, engineering, and math (STEM) education, a current teaching approach with the important momentum. Based on the epistemological stance of Larry Laudan, three levels of scientific commitment are adopted: with theories, methods, and aims. Regarding the theoretical commitment, three axes of support are established for this framework: epistemological, psychological, and didactical. This mechanism allows us to construct a consistent model that may contribute to developing coherent integrated STEM education. In addition, an example of a real application of this theoretical framework is provided in the design, implementation, and evaluation of a STEM didactic unit in the primary education stage, demonstrating its coherence and viability.