This graduation project focusses on the circular economy as a broader topic and stimulating specific circular behaviour within adolescents as a scope. The municipality has a specific division called Rotterdam Circulair tasked with the assignment of accelerating the city of Rotterdam towards a circular economy. The designer of this project has done extensive research into the target group of adolescents 11 -15 years old (early adolescence) and has found a couple of interesting facts. This age group does not know the concept of circular economy, is highly influential through their peers and parents and are still conducting non-circular behaviours such as littering on the street and wasting food at school. In order to stimulate the right kind of behaviour (refusing to buy excessive products, sharing more products amongst each other and buying more experiences than products) different concepts have been designed. A short term-strategy concept is an escape van, in which all elements are in the theme of a circular economy and every action causes a respective reaction as also happens in real life on the environment. This van serves as a promotional van which can drive to any location in the city. Another short-term concept is a minimal emission game, in which the players ultimate goal is to finish the quest without using raw materials or by minimizing their CO2 emissions. This game can be played online and is promoted on the platform of the municipality. The third concept is a long term one, in which a special addition is added to the already existing Rotterdampas. A new valuta, the golden ‘Deelders’ is granted to everyone which experiences an activity in the city. With these Deelders the holder of the card can vote on green and circular projects online on the website of Rotterdampas. The projects with the most votes will receive funding of the municipality and will be carried out. This concept stimulates a democratic system where citizens are more actively involved in the sustainable aims of the municipality. Next to the concepts, 30 + ideas where turned into an idea card deck which can be used by the municipality in future creative sessions or projects. Critical criteria for designing for the target group are grouped in a list and can serve as future knowledge when carrying out a project for this specific age group. An estimation of the business model of each concept is explained in detail, as well as a mini timeline in correspondence with the timeline of strategy of Rotterdam Circulair. The project concludes with a few recommendations for the municipality as to how they could proceed in the future: involving their target group more in sessions, using the idea card deck for inspiration and involving multiple divisions of the municipality to make the concepts work.