“Sustainability: Think Globally - Act Locally” was planned as a two year long project originating in the idea of developing a sustainable change in the way of thinking, a more respectful behaviour and an improvement of STEM and CLIL skills. The issue of sustainability is very present and our everyday choices have an impact on the future. A sustainable change must happen among the whole population because it is a common concern. One of our most significant tasks as teachers is to educate young people in critical thinking about current and upcoming problems. The participating schools and nations are facing similar challenges and only together we are able to protect nature for future generations. Our aim is to find solutions and give an insight into ongoing projects which could protect our environment through active learning activities and by comparing regional challenges. To support the local community as well as the European one, it is important to implement and widen critical thinking and negotiating solutions.In this project schools from six countries (Germany, Italy, Finland, Portugal, Belgium and Netherlands) with an active working group of 35 teachers and 250 students came together. We worked on global and local aspects of sustainability with content related focus as well as e-skills and CLIL skills. The Partners are members in programs like “Eco-Schools” “Europaschule” “NUFFIC” and “MINT EC”.As our project topic is a wide one, we decided to divide it into blocks. The content related blocks were geothermal energy, forestry, biomass energy, solar energy, wind energy, water energy, utilisation and purification of water, utilisation of plastic and electronic waste. Each country had a specification so we were able to create targeted questions and tasks on which the students worked. We led them to work in international groups to ensure their improvement of English skills and international understanding (CLIL). Only during the preparations for each trip they worked in their national school groups. Our activities consisted of visiting local partners who gave insight into ongoing projects and possible solutions for sustainable ways and active working parts during the activities. We worked with a lot of local partners and had exciting and interesting study trips. We produced our own solar cars, saw a few hundred meter deep digging holes, walked through a coal mine, worked in the forest and planted new trees, felt the power of water, had an olfactory experience in a water purification station, felt the hight of a wind wheel, created a mobile solar charging station. These are a few highlights we experienced during our project. We created an interactive book including working results which is linked to our project homepage where all our activities can be seen, local partners can be found and working results are listed. Students created lessons which can be used by teachers and students who want to work on the topic. We built a mobile solar station for usage by all students, the building instructions are online to provide the possibility to rebuild it. It was a beneficial experience for all of us to be part of a multicultural team. Not only the students but also the teachers learned a lot during this project. It was a very fruitful partnership and we are already planning to continue our partnership in new projects. If you would like to read more please visit our website: https://trello.com/b/KfnFykIi/think-globally-act-locally-erasmus-projecthomepage