The rapid expansion of technology and the internet has changed how we access and interact with information as a society. Amid this phenomenon, people of all ages and backgrounds struggle to evaluate the credibility of information they encounter online, including teachers. In order to ensure that the next generation of K-12 students are digitally literate, teacher education programs have a responsibility to improve preservice teachers' civic online reasoning (COR) abilities. Curricular interventions that teach COR strategies have shown potential in improving students' ability to detect misinformation online. This paper explores how a digital literacy intervention in an educational technology course impacted preservice teachers' COR abilities, strategies, and perceptions. Findings revealed that after the intervention, preservice teachers' COR abilities improved, their evaluation strategies evolved from content- to context-related, and their perceptions of scientific merit shifted from a surface-level understanding to a more critical perspective. This paper provides practical and scalable curricular recommendations for teacher educators and highlights the value of integrating COR interventions with sociocultural literacy theories.