The transition from secondary to higher education remains problematic given low retention figures in science courses, in particular in open-enrolment universities. Adjustment to a new learning environment and dealing with the mass experience are factors at play. We looked for ways to ease the adjustment and to moderate the mass experience by creating a moderate-structure Cell Biology course, characterized by broup-based activities, frequent in-course assessment and reduced weighting of the final exam score. Comparison of 4 years of low-structure with 4 years of moderate-structure courses, after corretion for annual cohort ability, revealed that moderate-structure yields 8% higher grade points and 5% higher retention. However, the overall gain in performance was largely dependent on in-course scores and improvements were only weak for the final exam. The frequency of students underperforming on the final exam, relative to their in-course scores, increased enormously in moderate-structure courses, rom 53 to 90.3%. We see this as a sign that for a substantial number of students, the final exam remained a destructive friction. As a result, we are still dealing with a population that has not assimilated a considerable portion of the Cell Biology knowledge and is starting the second year with significant gaps.