In this study, the effect of internet-based applications on the academic achievement, motivation, and awareness of Web 2.0 tools of 6th grade middle school students on "Matter and Heat" was examined. The study group consisted of 73 (experimental: 50, control: 23) 6th grade students from a public school in Istanbul, Turkey. The study was conducted with an experimental design with pretest-posttest control group among quantitative research models. In the experimental group, science lessons were taught with the support of web 2.0 tools such as Nearpod, Canva and Quizizz, while in the control group, no additional application was made and the lessons were taught as specified in the curriculum. The data of the study were collected with the "Motivation Scale in Science Education", "Matter and Heat Achievement Test" and "Awareness Scale for Web 2.0 Tools". T-test and one-way factor analysis (ANCOVA) test were used to analyze the data. The results of this study showed that the academic achievement test scores of the experimental group students were higher than the control group and there was a significant difference between the academic achievement test scores of the experimental and control groups. The results showed that the science motivation scores showed a significant difference in favor of the experimental group and the science motivation scores of the experimental group students who were supported with web-based applications were higher than the control group. In addition, according to the results of the one-way analysis of covariance regarding the awareness of web 2.0 tools, there was a significant difference between the experimental group and the control group in favor of the experimental group in the post-test scores. In this study, the importance of planning and implementing science lessons supported by internet-based applications at the secondary school level was revealed.