In the basement of Harvard Business School’s Aldrich building at 9am, 90 chattering first-year MBA students file into a semi-circular amphitheatre and take their pre-assigned places, marked by name cards. They are about to participate in the Finance 1 course, one of their first experiences of the institution’s signature approach to teaching and research.

Each student lays out in front of them a case: a stapled booklet containing a dozen or more pages of text interspersed with data. Many have scribbled and highlighted sections on the paper, symbols of their debates and calculations from the “learning teams” in which they prepare for classes in small groups.

During two years of study, the typical student will analyse and discuss 500 cases: a pedagogical approach that has achieved near-religious status at Harvard and proved highly lucrative with sales to hundreds of business schools around the world. But case studies are now being written in varied ways, or rejected outright by rivals as business education trends shift.