Faced with worsening environmental degradation in Brazil, indigenous communities, representing a rich diversity of ethnicities and worldviews, have felt and resisted various impacts. This study aims to discuss indigenous university students’ experiences, from different ethnicities, concerning sustainable green technologies in dialogue with Critical Theory references and critical environmental education. Therefore, excerpts taken from interviews and focus groups related to sustainable green technologies were selected. After having recently implemented affirmative action policies, the Federal University of São Carlos (UFSCar) has systematically attracted students from hundreds of Brazilian indigenous ethnic groups. In 2019, research was conducted with indigenous university students from UFSCar from three areas of knowledge. It was found that in their communities of origin, agricultural practices and sustainable management are maintained; many of them based on ancient ancestral knowledge. The reports indicate that there is almost no use of pesticides and synthetic (chemical) fertilisers. Indigenous university students’ experiences of cultivating soil associated with the food security of their people can also be observed, which is of central importance nowadays, similar to the Farm to Fork Strategy proposals (a component of the European Green Deal).