FIBER (Flipped Issue-Based Enquiry Ride) is a teacher-facilitated interactive pedagogic framework that the authors propose to integrate flipped learning into social humanities education. This paper reports a quasi-experimental study (with mixed methods) which examined the pedagogic effectiveness of FIBER in the authentic setting of formal curriculum learning and teaching. The study involved totally 611 Secondary-4 students from academically top, middle and bottom schools in Hong Kong. In comparison with the conventional issue-based enquiry learning approach, FIBER had different intensity of positive effects on the high, moderate, and low academic-achieving student participants. This paper provides researchers and educational practitioners with empirical evidence for supporting wider adoption of FIBER in social humanities education, as well as harnessing flipped learning in formal schooling. Apart from discussing the benefits, the authors also underline the challenges of FIBER and suggest future work.