STEAM + X - Extending the transdisciplinary of STEAM-based educational approaches: A theoretical contribution.

• Ideas for applying transdisciplinary STEAM practices. • Design-based research methodological contributions. • Design Principles- actionable knowledge. • Transdisciplinary theoretical framework STEAM +X. • Mathematics teacher's professional development. • Cross-cultural applications. • Technology integration. • Enhance learners' 21st Century Skills such as thinking skills, creativity, problem-solving. This design-based research methodological paper is proposing a theoretical understanding in the form of STEAM + X framework that emerged from the empirical findings of implementing transdisciplinary STEAM practices featuring architecture, culture, and history. This paper shows how the proposed STEAM practices, involving creativities, to promote the integration of various disciplines with multiple cross-cultural iterations. These STEAM practices allow teachers to integrate cultural, architectural, environmental, or technological options into mathematics teaching and learning. These STEAM practices foster creativity and thinking skills in connecting disciplines in a transdisciplinary learning approach. Moreover, this paper introduces the study outcomes including the developed design principles and a framework that connects the underlying theoretical framework with emerging themes from our qualitative data analysis. [Display omitted] [ABSTRACT FROM AUTHOR]