The planetary crisis is undeniably urgent, as highlighted by the IPCC (Intergovernmental Panel on Climate Change), which warns that impacts of climate crises on our planet are even more significant than previously estimated, leading to irreversible damage and irreparable losses to ecosystems (IPCC, (Climate change 2023: Synthesis report. Contribution of working groups I, II and III to the sixth assessment report of the intergovernmental panel on climate change [Core writing team, H Lee, J Romero (Eds)]. (2023) https://doi.org/10.59327/IPCC/AR6-9789291691647). Human activities have drastically altered around 75% of the land and 66% of marine ecosystems, resulting in overall decreases in ecosystem size by about 47% (United Nations Environment Programme (UNEP) (Enfoques integrados en acción: Un complemento de los principios internacionales de buenas prácticas para una infraestructura sostenible, 2021)). Over 85% of wetlands have disappeared, and 32% of the global forest area has been lost (IPBES (Global assessment report on biodiversity and ecosystem services, 2019)). Protecting and restoring wetlands is crucial, as they serve as greenhouse gas sinks and mitigate climate risks. Besides, they are significant ecosystems within the environment, offering a wide range of benefits for both humans and various forms of aquatic and terrestrial life. Failure to take decisive climate action based on eco-justice poses one of the most severe risks for the coming decade (World Economic Forum, 2025). In this chapter, we discuss eco-justice challenges through environmental activism, presenting the case of two science teachers who are authors of this chapter. One is an experienced teacher living in a Chilean region with a relevant wetland zone affected by extractivist practices. The second is a beginning teacher questioning her practices as a science teacher in another zone in Chile affected by environmental conflicts. As a research group, we reflect on critical dialogues between these two teachers working in Chilean schools. Our analysis encapsulates discussions on four challenges, aiming to identify opportunities for activism within science education.