Engineering students (N = 285) enrolled in either a first-year or senior-year design course that consisted entirely of team-based collaborative learning projects reported few gains in their overall leadership development. First-year students made moderate gains in transformational leadership skills and social-normative motivation to lead. Peer evaluations of skill were lower than were self-reported scores, and, for first-year students, self-reported scores and peer scores were not correlated. A high degree of co-curricular involvement in student organizations, as compared to little or no involvement, was associated with student gains in seniors. These results indicate the relatively small degree of leadership learning that takes place in classroom-based team experiences when those experiences are not paired with opportunities for deliberate practice or reflection in the development of leadership capacity.