Media and Information Literacy (MIL) education can combat online misinformation by enhancing users' fact-checking skills. This action research study designed and implemented a problem-based learning MIL project for journalism undergraduates. The objectives are (a) to design a MIL project by using a problem-based learning methodology; (b) to implement the MIL project and to assess its effectiveness in improving students' fact-checking skills; and (c) to identify the challenges and limitations of implementing the project. Analysis shows that the MIL project successfully improved students' MIL skills, including critical analysis, media production, and personal growth. Despite facing challenges like time constraint and limited generalizability, the study suggests that the MIL project could be replicated in other journalism programs to enhance MIL skills and cultivate critical thinking to fight misinformation.