Young people are the citizens of tomorrow. To become fully responsible and involved in their environment, it is necessary to pass on their keys to better understand the world around them. The goal of the project is to promote the awakening of an eco-citizen conscience by providing students with a foundation of knowledge to help them become aware of the issues related to sustainable development and encourage the emergence of eco-citizen behaviors.This project involved 3 institutions located in Italy, Croatia and France and directly addressed nearly 100 high school students, all technological and general sectors, who wanted to work on a common European project.The project allowed students to take ownership of the issues of sustainable development and propose concrete actions to preserve the environment and initiate a lasting change in behavior.For eco-gestures to become reflexes, it is still necessary that all high school students understand the issues of sustainable development and acquire the skills and knowledge both transversal and scientific related to it. It was the ambition of Workshop 1, I want to understand the issues.As part of Workshop 2, the students went in search of good experiences and met with local actors of sustainable development, these positive experiences were put end to end in the frame of reports to show that the development sustainable development is everyone's business and that the main principles can be applied in our territories and that we have gathered a good number of positive experiences to disseminate to inspire a maximum of people.Beyond the awareness, it is now to promote the development of eco-friendly family or eco-responsible behaviors within our institutions. In workshop 3, students were asked to become individually and collectively involved in concrete action with their families, high school and / or at their city / village / neighborhood level to respond to sustainable development issues. To participate in the emergence of such initiatives, the teaching team has favored educational resources that mobilize new active and practical approaches rooted in the digital age.The students carried out actions to make known and recognize their actions to change behavior. As ambassadors, they had to raise awareness, inform and convince the maximum number of students, parents, teachers and local actors (local elected representatives, local populations, local businesses, associations ....) ..... to adopt eco-friendly gestures.The priority of this strategic project was to develop a scientific and prospective approach, allowing each citizen to make his choices and his commitments by supporting them with a lucid and enlightened reflection. As informed, thoughtful and more accountable citizens, students will be able to play an effective role in society. The students were able to deepen their scientific knowledge in the humanities and social sciences as well as the natural sciences and engineering. They also havedeveloped their cultural and social openness especially through educational stays and skype exchanges. This project generated interest in foreign languages ​​(Italian, English, French) and promoted the use of new information and communications technologies. Teachers have also been able to discover and introduce other educational systems, some have even changed their teaching practices and thereby developed their European identity and their language skills.