The design thinking approach, commonly used in product development, is important in identifying and eliminating problems or deficiencies, especially in educational settings. Using contemporary approaches such as design thinking in these processes will enable innovative solutions to emerge. In this study, which focuses on the effectiveness of the products developed in the design thinking process, it is aimed to reveal the effect of the products used in the experimental process on the academic achievement and students' views on the process. Sequential explanatory design, one of the mixed research designs, was used in the study. The study used a quasi-experimental and control groups design in the quantitative phase and phenomenology in the qualitative phase. The sample consisted of middle school sixth-grade students. The data were collected using the “Electronic Century” Achievement Test and a semi-structured interview form. The qualitative data were analysed using content analysis and the quantitative data were analysed using the Mann-Whitney U test and the Wilcoxon signed-rank test. The analysis results showed a statistically significant difference between the scores obtained at the end of the design thinking-based product development process and the scores obtained at the end of the curriculum-based process. In other words, the products used in the experimental process positively affected the academic achievement. In addition, the experimental group held the view that the design thinking-based product development process facilitated learning, involved games and made the course fun.