The growing world population is gradually disrupting the balance of the natural world and the environment. Unawareness and improper use of resources contribute to environmental imbalances, leading to ecological problems. To prevent or address these issues, it is crucial for individuals to possess a certain level of ecological citizenship. It is found that there is no scale aiming to assess the level of adolescents‘ ecological citizenship. The purpose of the research conducted is to develop a valid and reliable tool to assess the ecological citizenship levels of adolescents. As part of this goal, a literature review on ecology and ecological citizenship was carried out. The Ecological Citizenship scale was originally developed for adolescents ages 14–17 years old and was presented as valuable for comparing that age group with older participants. This study aims to assess the validity evidence of the Ecological Citizenship Scale (ECS) designed for adolescents. The scale comprises three key constructs: Knowledge, Responsibility and Duty, and Behaviour. This paper presents the results of factor analysis, internal consistency reliability, and normality tests, demonstrating the validity and reliability of the scale. Findings indicate that the ECS exhibits strong internal consistency, with high Cronbach’s alpha values across the components, and provides an empirically grounded measure of ecological citizenship for adolescents.  Read more