Integrated "Science, Technology, Engineering, and Mathematics" (STEM) education is recognised as the latest development stage on the pathway to a highly capable future workforce, and is thus linked to a nation's future development and prosperity. However, despite various appeals and efforts by the Australian Government, effective processes for constructing relevant educational programs within local curricula remain under-researched. A comprehensive review of the design, and design-led education literature, and of related attempts to develop suitable instructional content and approaches, has been conducted. Its outcome is a recommendation to adopt a design-based pedagogy utilising 3D printing for the development and implementation of integrated STEM programs. Accordingly, this paper proposes a new area of research that requires a deep understanding of appropriate design processes, skills, and mindsets, for integrated STEM education. This study also prototypes a design-led conceptual framework to assist educators in developing integrated STEM programs. Based on the learning theory of Distributed Cognition and the Four-component Instructional Design (4C/ID) model, this conceptual framework begins to address an urgent need to prioritise methodologically rigorous evidence-based research on integrated STEM education. It also has the potential to lead to the formation and collaboration of STEM education communities of teachers, students, and researchers as external instructional leaders to co-develop design-led integrated STEM curriculum.