AbstractLow concept understanding and misconceptions often occur in physics learning, including concepts on elasticity. On the other hand, there are not many available IT-based teaching materials that support 21st century online learning that can improve understanding of concepts. Therefore, it is important to develop interesting IT-based teaching materials that can improve understanding of concepts and remediate students' misconceptions. This study aims to produce valid cognitive conflict-based interactive multimedia. This type of research is development/design research using the Plomp model. This article reports the results of the development phase, namely prototype design, self evaluation and expert review. The instrument collects data using a self-evaluation sheet and a validation sheet. The validity data were analyzed using the V-Aiken formula.Based on the results of the preliminary research, interactive multimedia has been designed with the following characteristics: composed of 4 syntax.....