This paper considers this issue critically and seeks to illustrate how a reflexive, model for change oriented professional learning of teachers in environment and sustainability education has potential to influence teacher education practice (Mandikonza, 2016; Mandikonza and Lotz-Sisitka, 2016). Of interest is the way in which the focus on a ‘change project’, designed as a central, expansive learning mediation tool in the courses, was carried into workplaces with various structural (SEPs), cultural (CEPs) and people emergent properties (PEPs) (Archer, 1995). Archer’s (1995) morphogenic theory, helped us to show that capacity for mainstreaming environment and sustainability education can be facilitated through a praxis-located course mediated process. Here we found that reflexive processes that focused on the mainstreaming of environment and sustainability as a learning process, were framed by, structured and woven around the change project as the organizing framework. To this end, as illustrated in this paper, the change project was an important mediating tool that was used to challenge normalized practices and create opportunities for transformed teacher education practice towards environment and sustainability education in teacher education contexts. We understood practice as manifesting in mentally situated and technical forms, also known as habitus (Bourdieu, 1998); it also included Kemmis’s (2009) perspective of doings, sayings and relatings, as well as enhanced sustainability competences and capabilities for mainstreaming environment and sustainability education. Transformed teacher education practices towards environment and sustainability education constituted aspects of the expanded zone of proximal development of the teacher educators in the social reality of institutional practice. Findings pointed to course participants having enhanced individual knowledge, skills and agency around mainstreaming of Education for Sustainable Development. Participants showed enhanced ability to work more in collaboration with others in and outside their institutions. Participants also demonstrated ability to work with national, regional and international networks such as EEASA and UNESCO on Education for Sustainable Development. At the individual level, change projects were conducted differently as a consequence of matters of concern identified by the course participants and the enabling or constraining factors in institutional contexts (Mickelsson and Mandikonza, in press). The course therefore influenced scaling at individual, institutional, national, regional and international levels. We deduced that scaling through the change project approach therefore tends to be both generic and contextually influenced. Generic scaling is the scaling of the notion of ESD in the general sense. Contextual scaling describes the way the individual change projects are implemented and turn out.