The present study aimed to investigate the impact of the problem-based learning method used in science and technology teaching upon elementary school students' construction levels for the concepts concerning the "Systems in Our Body" unit in the science and technology course and their academic achievement. To this end, during the four-week experimental application process, the course was taught using the problem-based learning method in the experimental group and the control group curriculum was only based on the science and technology textbook. The study used two groups including the experimental (n = 20) and control (n = 21) groups, and the study used the pretest posttest control group semi-experimental design. The analysis of the obtained data revealed a significant difference in favor of the experimental group on students' scores on the academic achievement test and the open-ended questions that identified their construction levels for the concepts. This study should guide further studies and to help determine the effectiveness of the method in question on elementary school students. (Contains 9 tables.)