<![CDATA[Biology education examines various environmental issues, including coastal ecosystem degradation, which reflects the lack of human character or concern for the environment. The low level of knowledge and environmental awareness among students regarding coastal ecosystems may be caused by insufficient education and the lack of appropriate learning materials. This study aims to develop the Digital Booklet on Coastal Ecosystems (DICE) as a valid, feasible, and effective teaching material to enhance students’ environmental awareness. The research employed the ADDIE development model, which consists of five stages, analysis, design, development, implementation, and evaluation. Data collection techniques involved non-test instruments (student needs analysis questionnaires, expert validation sheets, readability questionnaires, and environmental awareness attitude scales), as well as interviews (teacher needs analysis). The sample consisted of 9 students for the small-group trial and 31 students for the large-group trial, selected using simple random sampling. Data analysis was conducted using a paired sample t-test and normalized gain (n-gain). The validation results from two biology education experts yielded a score of 3.27 (very valid). The readability tests conducted by students and teachers met the required assessment criteria, indicating that the teaching material is feasible for use in learning. The hypothesis test yielded a significance level of p < 0.005, indicating a statistically significant difference between the pre-test and post-test scores. The gain score was 0.57 (moderate improvement), and the normalized gain effectiveness was 57% (moderately effective). In conclusion, DICE was successfully developed as a valid, feasible, and moderately effective teaching material for improving students’ environmental awareness.]]>
