The present study aimed to investigate the effectiveness of environmental education in the form of a zero waste plan on improving environmental awareness, attitudes, and behaviors of elementary school students, as well as the role of family participation in sustaining these behavioral changes. This study was conducted with a quasi-experimental approach and in a real school setting, on a group of male and female students in the second and third grades of elementary school in Ardakan city.Data were collected through three main sources, including direct observation of behavior, structured surveys, and analysis of documents and student works, and analyzed using a combination of quantitative and qualitative methods. In order to increase the validity of the findings, the approach of data triangulation and standardization of indicators in the form of comparable scales was used. The research findings showed that implementing the zero waste plan significantly increased awareness and improved students' environmental attitudes, and these changes were also significantly reflected in the level of behavior.Reducing the consumption of single-use plastics, increasing the use of reusable tools, and promoting participation in waste separation were among the most important behavioral changes observed. The results also showed that the formation of environmental support groups in schools played an important role in strengthening social capital and sustaining environmental behaviors. Another important finding of the research was the decisive role of families in establishing and maintaining students' environmental behaviors, such that the alignment of school education and family behaviors has reduced the gap between awareness and action.