Integrating Ocean Literacy into Secondary Education through Gamification: The Case of Marine Dobble

The accelerated loss of biodiversity and the limited integration of ocean literacy into school curricula highlight the urgent need for innovative approaches in Environmental Education for Sustainability (EES). This study presents the design and implementation of Marine Dobble, a gamified educational tool inspired by the popular card game Dobble, adapted with illustrations of marine species from the Andalusian coast (Spain). The aim was to foster knowledge, awareness, and commitment toward marine biodiversity conservation among secondary school students. The intervention was conducted in five 1st-year ESO classes (n = 110, ages 12–13) in Cádiz, Spain, through a one-hour workshop facilitated by an environmental educator. A qualitative exploratory design was employed, using observation chronicles to record students’ participation, reactions, and learning evidence. The activity combined fast-paced gameplay with five reflective “pauses” addressing key concepts: marine habitats, species adaptations, scientific curiosities, environmental problems, and personal commitment. Results show high levels of motivation, participation, and engagement, with notable emotional and cognitive responses to less-known contents, such as the ecological role of microalgae and the existence of marine plants. Students progressively improved their use of scientific terms and formulated concrete actions for ocean conservation, including reducing plastic waste and promoting sustainable consumption. Differences among groups highlighted the importance of teacher involvement and classroom climate. This study concludes that gamification, when contextualized and combined with reflective dialogue, is an effective strategy to integrate ocean literacy into secondary education. Marine Dobble proves to be a replicable tool that fosters meaningful learning, environmental awareness, and pro-sustainability attitudes in young learners.