Complexities of social problems in our globalised world pose new educational challenges, including how to empower citizens for active engagement with socioscientific issues. This study describes the analysis and discussion of an activist video as the first phase in an activist education programme. Participants were 104 preservice primary teachers from the University of Malaga (Spain). Their task was to watch a video about illegal mining in the Venezuelan Amazon and, using the "CoAnnotation" tool, to annotate the video so as to indicate: the problem they saw as most important, the best solution and ways in which the video could be improved. Students were subsequently shown all the annotations that had been made by the group as a whole so as to facilitate discussion. The content of their annotations was analysed and described using a category system developed by consensus among the research team. The problem most commonly referred to by students was environmental damage. In terms of solutions, the main focus was on raising awareness, although mention was also made of government intervention and both citizen-led and school-based initiatives. As for how the video might be improved as a tool for raising awareness, students made several suggestions regarding its content.