The development of environmental science agency (ESA) is considered very important for the sustainability and conservation of the environment and the safeguarding of the cultural heritage. It is enhanced through experiential programmes and participatory actions that shape future environmental behaviour. ESA consists of three components: knowledge, role development and agency about the environment and the current issues affecting it. The present research was designed to explore how an environmental entrepreneurship intervention programme with primary school students can promote the development of their ESA. The study involved 34 primary students, aged 11–12, who participated in an environmental entrepreneurship educational programme. It follows a mixed methods design using quantitative and qualitative methods of data collection and analysis, namely pre- and post-students’ questionnaires and teachers’ interviews. The results indicate the development of knowledge and roles components, while the third component, agency, seems to diminish. The results of this study seem to be suggesting that late childhood is a good period to invest in the development of ESA, by offering environmental entrepreneurial programmes to students that might leverage their future intentions and willingness in taking action towards the sustainability of the environment and the cultural heritage. Future studies should continue to investigate the relationship between environmental entrepreneurship education and the development of ESA.