Marine biodiversity research often remains inaccessible to the public despite increasing interest in ocean sustainability and conservation. Translating scientific research into engaging learning experiences is essential for strengthening ocean literacy and encouraging active participation in marine stewardship. From December 2023 to November 2025, a jellyfish monitoring and Blue Citizenship initiative was implemented in Penang, Malaysia with support from the Blue Partnership Action Fund (BPAF), Society of Entrepreneurs and Ecology Foundation (SEE Foundation) to evaluate how long-term marine research can be integrated with citizen science and public engagement. The programme combined 11 jellyfish monitoring expeditions and two outreach programmes, involving 302 participants from 11 local and international institutions, including schools, universities, research organisations, and community groups. Participants received practical training using simplified sampling protocols, jellyfish identification guides, and standard operating procedures before participating in field observations, specimen identification, and discussions on marine biodiversity, coastal ecosystems, and responsible ocean stewardship. Preliminary observations recorded eight jellyfish taxa, with Chrysaora chinensis consistently dominating the assemblage (approximately 80–90% of all recorded individuals), while several other scyphozoan and cubozoan species were documented throughout the monitoring period. Seasonal variation in jellyfish occurrence provided an authentic scientific foundation for public engagement activities, allowing participants to experience how long-term ecological monitoring contributes to understanding tropical coastal ecosystems. Rather than presenting jellyfish solely as organisms associated with harmful stings, the programme reframed them as ambassadors for marine biodiversity and ocean conservation. Direct participation in field sampling fostered meaningful interactions between scientists and the public, transforming scientific data collection into an experiential learning platform that stimulated curiosity, dialogue, and environmental stewardship. This study demonstrates that integrating long-term ecological monitoring with citizen science provides an effective model for science communication and ocean literacy. The experience gained highlights the value of participatory marine research in strengthening Blue Citizenship and offers a practical framework that can be adapted by other coastal communities seeking to connect science with society.