Background: The conceptions that children develop about environmental issues are likely to form the basis of how they comprehend such issues, influence their behaviour towards the environment and, ultimately, determine the way they address these issues. Being aware of children's ways of thinking about the environment is, therefore, of paramount importance if educators are to provide effective and efficient teaching in this field of increasing global significance. Purpose: This paper presents an explorative study which sets out to identify the dominant conceptions held by a sample of 9-year-old students in relation to addressing, both collectively and individually, two environmental issues, namely forest destruction and waste. Sample: The sample comprised 30 9-year-old students (15 boys and 15 girls), from 2 state primary schools with diverse socio-economic student populations, in a provincial city in central Greece. Methods: Semi-structured interviews were used to collect the data. The interviews were analysed qualitatively, using a thematic approach. Results: Findings suggested that children's conceptions about how to address environmental problems could be grouped into two broad conceptions: the first concerned proposing 'direct actions' for the short-term addressing of the problems, whereas the second related to a proactive approach for addressing the problem in the longer term, with an emphasis on sustainability. Furthermore, there seemed to be connections evident between the children's conceptions in terms of their personal contributions and the thoughts they held about collective actions. Conclusions: This study offers insights into children's approaches to addressing the problems of forest destruction and waste. It was evident that the children believed that they could address the problems by applying whatever methods they are aware of. We argue that this suggests that an action-oriented and problem-solving strategy towards education would be beneficial. A transformative approach is suggested as an effective technique, drawing on hands-on, experiential and project-based activities, so that children can be educated with the aim of becoming competent at making decisions themselves and taking action as active participants and change agents for sustainability.