Visit the campus office of student life or office of student activities, and ask for a list of school-sponsored clubs. Joining a student association can provide a forum for making friends and having discussions on any number of interesting topics. Most colleges and universities sponsor student associations specifically focused on themes such as religion or political parties, which can be a way to meet like-minded students.
Visit professors and instructors during office hours posted on class syllabi. Many professors are willing to engage in dialogue about challenging topics with students outside the classroom. Building mentoring relationships with professors can be beneficial, as they have performed extensive research in their specialties and can often recommend additional books, articles and websites.
Follow the campus newspaper to learn about school-sponsored events. Many campuses will hold screenings of documentaries or even forums with experts to debate any number of hot topics. These films and forums can facilitate challenging dialogue about popular topics both locally and worldwide.
Talk to professors and student life professionals about forming a new student group if there are no clubs or events relevant to your topic of interest. Chances are there are other students eager to discuss hot topics on campus. Forming a new group can also provide invaluable leadership experience.