The aim of this study was to examine the quality of the written argument of pre-service science teachers on certain socio-scientific issues (SSI) and their opinions about the process of something. The study group consisted of 26 pre-service science teachers (18 females and 8 males) studying in their 3rd year of a state university. The purposeful sampling method was used for the study. In the study, a case study pattern was adopted from qualitative research designs. The study was instructed with the YouTube social media supported classroom discussion process. The data sources of the study consisted of sugar loading in pregnancy, raw/loose milk, and processed/pasteurized milk, written arguments for the SSI of the nuclear power plant, pre-service science teachers' journals, researcher notes, and semistructured focus group interviews. The data obtained in the study were analyzed based on descriptive and content analysis techniques. The results of the study indicated that the quality of argument increased significantly during the implementation of something when the written arguments of pre-service science teachers were examined after class discussion. In the evaluation of the research process, it was determined that pre-service teachers' awareness of the SSI and the YouTube supported classroom discussion process contributed positively to life skills and science process skills such as decision-making, hypothesis building, discussion, and analytical thinking.