<![CDATA[This study aims to develop web-based mathematics learning media using Linktree for the topic of 3D shapes (geometric solids) for fifth-grade elementary school students, and to determine its validity, practicality, and effectiveness. The study employs the 4D development model (Define, Design, Development, Disseminate). The research subjects consisted of 20 fifth-grade students from SDN 065853 Denai. Data collection techniques included interviews, observations, questionnaires, and tests, while data analysis involved both qualitative and quantitative methods. The results indicate that (1) the web-based learning media using Linktree was deemed valid, with validation scores of 82.2% from the subject matter expert and 92.7% from the media expert, falling under the "highly feasible" criterion; (2) the Linktree learning media was considered practical based on teacher responses, achieving a 90% rating which falls under the "highly practical" criterion; and (3) the Linktree learning media was proven effective, as evidenced by an improvement in student learning outcomes, where the average score rose from 46.75% in the pre-test to 87.00% in the post-test. Furthermore, the dissemination stage showed an increase from 46.75% to 87.00%, with an N-Gain score of 0.76 (or 76%), placing it in the high category. Thus, the web-based learning media using Linktree is proven to be valid, practical, and effective for teaching 3D shapes in elementary school mathematics and is capable of significantly improving student learning outcomes. Keywords: Web-based learning media via Linktree, Mathematics, 3D shapes, learning outcomes, 4-D development model.]]>
