This research considers a reflective observation towards paradigm shifts in the flows of ideas and modelizations from process development to project development in the context interior design engineering studio education highly impacted by global environmental issues considerations and the need to consider emerging necessary interconnections between a STEM-based design, CAD-based Learning and Design Thinking for a Sustainability in Design Education. Such paradigm shifts are linked to evolving new conceptual, technical and technological approaches and models amongst reinvented pedagogical contents, CAD tools and creativity tools in a design studio. The core parameter is the examination of a significant alteration in the “thinking by doing” process that learners are facing throughout the interior design engineering project development phases. The creative work and the systematic scientific and engineering design work, as conceptually separable approaches in a design studio project, are presently supposed to be nearly “fused” to generate new challenges and modelizations concerning the ways of “experimenting the design by thinking” and “experimenting the design by doing”. As learners in interior design engineering project increasingly emphasize CAD tools and thinking tools almost waive synchronizing “fundamental” STEM components as powerful tools to achieve environmental aspects of the project, various questions and divergent examinations gain a foothold on the thinking phase development and the level of control over the design process implementation. As focused approach of this research, arranging CAD tools and STEM system to creativity tools towards sustainability considerations in an interior design engineering project seems to be manifested into two complex parameters that impact both the design process and the intended environmental qualities of the project. Accordingly, as per the implemented qualitative and quantitative methods the research finding will examine the potentialities to fuse and interconnect the different methodologies without confusing their particularities to achieve a comprehensive approach for a sustainability in design education.