In this research, an experimental study was carried out in social studies 4th grade students to develop students' conceptual achievement and motivation to succeed academically. The study aims to investigate the effectiveness of project-based learning (PBL) in social studies. A quasi-experimental research design (pre- and posttest) was used in the research. While the experimental group of students received an interactive social studies instruction including completely PBL in a team format activities, the control group students received an instruction including direct instruction method (whole class teaching and individual work in the worksheet of the topics) in the 4th grade social studies curriculum for six weeks. The findings indicated a statistically significant difference in favor of the experimental group on the concept achievement and motivation. Students who participated in the PBL environments not only enriched and expanded their knowledge but also achieved a higher level of motivation than the control group. The PBL in a team format activities were provided to promote the experimental group students' motivation to succeed academically and to develop their conceptual achievement. The results demonstrated that the PBL improved students' understanding regarding social studies concepts and helped them achieve the behaviours which were aimed academically. The experimental group's intended behaviours in academic motivation at the beginning of the experimental treatment turned into performed behaviours at the end.