The Open-Ended Learning model, also known as the open-ended learning approach, is a learning design that presents open-ended problems with various possible solutions. Its aim is to train and cultivate originality of ideas, creativity, high-level cognitive skills, critical thinking, communication-interaction, sharing, openness, and socialization. Through this learning design, it is hoped to develop students' critical thinking abilities in the millennial era, where access to information is readily available but not necessarily accurate, especially in matters related to religion. The research conducted is of a qualitative descriptive nature. The results of implementing the Open-Ended Learning model in Islamic Religious Education (PAI) can bring significant benefits in developing students' critical thinking abilities and fostering positive attitudes necessary for dealing with differences of opinion and diversity in religious contexts. However, it is important to consider supporting and hindering factors to optimize the effectiveness of this model in PAI education.