Development of Learning Media Using Desty Assisted by Desmos for the Quadratic Function in 9th Grade

The background of this research is the need for more interactive and visual learning media to help students understand abstract concepts, such as quadratic functions, which are often difficult to understand with conventional media. This research aims to develop technology-based mathematics learning media using the Desty platform assisted by Web Desmos on quadratic function material for grade 9 junior high school students. The method used in this research is Research and Development (R&D). The development of learning media was carried out through Thiagarajan's 4D model which consists of defining, designing, developing, and dissemination stages. This study only covers up to the development stage, where validation was conducted by experts without field trials due to restrictions caused by the COVID-19 pandemic. The results showed that the media developed were valid and feasible to use for learning, with the average validation results being in the valid category. The use of this media is expected to improve students' understanding of quadratic function material through clearer and interactive visualization.