This paper presents the evolution of a project-based course in Software Engineering for undergraduate students at the Universidad Nacional de Colombia. We describe and explain the changes we have done over six semesters. In addition, we investigate the effects of the changes on the students' grades and their project activities, by analyzing the software project repositories and the student feedback. Most of the changes had positive and expected results, while some had unexpected consequences. We distill a set of lessons regarding the class evolution, which will guide the future improvement of the course and which could be useful for other educators developing a similar course.