The Online Periodic Table of Elements (Ptable) is a Wikipedia-linked periodic table that displays a list of chemical elements organized by atomic number, electronic configuration, and recurring chemical properties. Elements are listed in reading order, increasing in atomic number, in their most basic form. The current study seeks to assess the impact of Ptable on students' understanding of trends in the properties of chemical elements. A mixed research strategy was used in this study. Chemistry students in grade eight (senior two) were selected to participate in this study. The sample size was 46 participants, with 38 students and 8 chemistry teachers chosen at random from two secondary schools in Bugesera District, in Rwanda. Interviews were used to collect qualitative data, which was then analyzed using discourse and interpretive analysis approaches. While quantitative data were collected by giving students achievement tests (pre- and post-test) and questionnaires, descriptive statistics were used to analyze them using a Statistical Package for Social Sciences (SPSS). According to the findings of this study, there was a statistical difference in student performance between the pre-and post-test, but no statistical difference between male and female students' academic performance. It was also discovered that students were pleased with the use of Ptable, which improved their learning and knowledge retention about trends in the properties of chemical elements. Teachers mentioned that Ptable is effective to teach trends in the properties of chemical elements. Among the difficulties noted were a slow internet connection and a limited number of computers.