Handayani T, Widiarti R, Soepardjo AH, Afriyani F, Burhanuddin E. 2017. The enhancement in comprehension for the younger generation of school age in conserving coastal biodiversity in Kepulauan Seribu, Indonesia. Ocean Life 1: 20-25. The exploration and exploitation can lead to the ecosystem and natural resources degradation. Kepulauan Seribu of Special Area of Jakarta has been extensively utilized and developed for tourism area, which could lead to the decreasing of environmental conditions. The awareness for keeping the ecosystem and marine life should be developed since early age. The objective of this research is to determine the level of understanding and ability in conserving the marine environment in their neighborhood for school-age generation. The method used in this study was quantitative with descriptive analysis. Two groups of the Junior High School students of Pulau Tidung and Pulau Harapan of the Kepulauan Seribu were provided training on conservation on coastal ecosystems. The education and training encompass the observation activity for coral reef using the Coral Health Chart method, seagrass condition observation through SeagrassWatch method, and introduction in the mangrove ecosystem. Based on the study, it can be inferred that the resulting activity indicated the level of understanding of cognitive abilities of two groups of the Junior High School in those two locations has increased. In addition, they affective ability increased sharply toward the students from Pulau Tidung whereas in Pulau Harapan an occurred a large increase in psychomotor abilities. The conclusion of this program is managed to improve the understanding and ability to act for the younger generation in conserving marine and coastal environments.