In early mathematics education, the beliefs of the teacher are essential for facilitating the integration of technology into teaching mathematics. This study explores the influence of physical and digital interactive learning environments on the development of early childhood teachers’ beliefs about integrating technology into early mathematics classrooms. To understand the development of teachers’ beliefs, a half-year, content-based professional development program that incorporates interactive digital and physical environments was designed for this research on early childhood mathematics teachers (N = 58). We administered a questionnaire to measure teachers’ beliefs regarding employing an interactive technological environment in mathematics classrooms before and after engaging in an intervention program. In addition, a reflective writing strategy was implemented with the participants (N = 10) to understand the development of their beliefs about technology via an evaluation of their levels of reflection. In general, the research findings indicate that an interactive learning environment supports an improvement in teachers’ beliefs about technology. Furthermore, positive qualitative findings were drawn from the reflective writing essays of early childhood teachers. The qualitative findings indicate that an interactive environment enables teachers to be conscious of selecting effective math-specific technologies that facilitate children’s exploration and discovery of mathematics concepts.