Many students are not good at geometric proofs. One reason for this is that it is possible to memorize the proof procedure explained by the teacher without understanding the structure of a geometric proof. So far, we have developed a web-based application that supports the understanding of the "structure of geometric proofs" in junior high school mathematics and have verified its effectiveness. Although the results of the evaluation experiments have indicated the usefulness of this web-based application, it was not possible to identify the factors that brought about its usefulness. In addition, because the web-based application was not equipped with a log analysis function, it was not possible to grasp the aspects that students struggle with during a proof in the web-based application. In this paper, we present the results and problems of the evaluation experiment of the web-based application so far and discuss the newly added log analysis function.