"Through international and intercultural friendship, young people should benefit from cultural diversity, through their actions today, help to preserve it for generations to come. Thus, while youth are the key to the future, it is essential that they shape the present too” (UNESCO, 2004). The purpose of this research is to analyze and describe the ways in which young people from many different countries and cultures experience their learning during an online course named Young Masters Programme (YMP) on Sustainable Development, provided by the university as an outreach activity. The focus is on the phenomenon Preventive Environmental Management Strategies as a tool offered to upper secondary school students for their knowledge formation and informed actions. The course is characterized as an extended global learning space in which the common content takes on a local meaning. A starting point is that through the distance course a global network is developed within which the students work across national and cultural boundaries, boundaries that have to be met and crossed across cultural differences. Different conceptions and different meanings of what are apparently similar concepts have to become the object of reflection, and this gives rise to knowledge formation (Pierce, 1934; Bateson, 1972). The different meetings encourage the young people to reflect more on attitudes, to realize how their own actions and the actions of other people affect the environment. The high school students work in interactions across the globe to learn about sustainable development through exploring a learning environment with new ICT-mediated ways of communication including global interaction with ideas and descriptions, and a transdisciplinary approach focusing on social, economic and ecological dimensions of the students’ daily lives (Gough, 1987). Young people from different countries and cultures were working with a common content in the extended classroom. These global meetings seem to catalyze the high school students’ commitment and learning process in a sustainable direction.