This paper describes how the use of free and open-source software (FOSS) can facilitate the application of constructive alignment theory in power systems engineering education by enabling the deep learning approach in power system analysis courses. With this aim, this paper describes the authors' approach in using the Power System Analysis Toolbox (PSAT) for undergraduate and graduate education. Interviews with former students reveal the positive impact that the use of FOSS in general, and PSAT in particular, had on their learning and how it has influenced their professional life. (Contains 3 figures.)