This paper examined socio-scientific issues-related literature in science education over the past two decades, from 2004 to 2023, to enhance researchers' understanding of research trends. To this end, the Scopus database was utilized to search for articles on socio-scientific issues published from 2004 to 2023. According to the inclusion and exclusion criteria, 288 articles were chosen for the data collection. The analysis was conducted utilizing VOSviewer software. The results show that the number of articles on socio-scientific issues in science education is steadily increasing. The most substantial growth in the number of articles was recorded in the last four years before 2024. The United States is the leader in the publication of articles. The number of citations demonstrates that the United States, Germany, and Sweden are the leading countries. The ten journals with the highest citations are ranked in the Q1 category. The research trends identified five clusters: a) decision-making, b) decision-making and argumentation practices, c) climate change, d) inquiry-based learning and the nature of science, and e) scientific literacy. Furthermore, the findings show that recent research in the context of socio-scientific issues has focused on STEM education. In light of the findings, I propose recommendations for future research.

Recently, in Indonesia, project-based learning (PjBL) has been used as an alternative approach in the teaching and learning process. Research on PjBL has been widely conducted in many countries at various levels. In most previous studies, PjBL was used to improve students' competence in certain math subjects. This study uses a case study research method to determine the effectiveness of PjBL at university in improving pre-service teachers' PCK. The research was carried out in 2022 involving fourteen mathematics education study program students selected by purposive sampling. The instruments used consisted of observation sheets, tests, and questionnaires. During the PjBL activity, participants were given a project to develop teaching materials for geometric transformation using certain teaching-learning strategies. The results of the study show that PjBL can improve students' PCK ability, although participants face several obstacles related to commitment to completing projects on time. Therefore, PjBL can be applied in the teaching-learning process to support professional mathematics teachers.