Individual differences in mental rotation are well-documented but poorly understood. In fact, how they evolve across lifespan still remains to be specified. To that purpose, we assessed mental rotation ability in Bachelor of Sciences and Bachelor of Arts American students, during their freshman year. They took the Mental Rotation Test twice, at the beginning and the end of the academic year. Results show significant effects of Academic Program (BS>BA) and gender (males>females) in both sessions, as expected from previous research. However, the Academic Program effect increased significantly from one session to another, with exposure to program-specific learning contents, whereas gender differences remained stable. These findings highlight the developmental effect on mental rotation in a single study, providing further evidence for the plasticity of spatial abilities in early adulthood and the need to reflect on the learning materials used in higher education institutions.