Fishing households in coastal East Lombok report falling catches under climate change, and the village rule systems that once regulated the sea have struggled to hold. Islamic religious education (Pendidikan Agama Islam, PAI) reaches Muslim children in these villages, yet it is unclear whether it draws on local ecological knowledge. This study asks what forms of ecological wisdom are documented in coastal and neighbouring Sasak communities, how Islam relates to them, how PAI currently carries ecological content, and what model of teaching material follows. It uses a qualitative interpretive case design in a field-study tradition. The case is built from published field evidence: 78 peer-reviewed articles with DOIs read from publisher pages, of which 49 were coded on six dimensions, and six books and chapters. No new primary data were collected. Reflexive thematic synthesis produced five findings. Only 14 of 49 coded studies concern coastal settings, and none of the 14 addresses a classroom or pesantren. Documented local institutions combine rules, ritual and moral messages, but in East Lombok the awig-awig has not withstood pressure. Islam aligns with local practice in some cases, is negotiated in others and is contested in three. PAI carries environmental content that is general rather than local. Transmission is helped by community partnership and weakened by structural pressure. The study proposes the Coastal Amanah Curriculum Model, with a normative filter based on custom (urf) and the objectives of Islamic law (maqasid), six testable propositions and a field protocol.