Typical software engineering courses teach principles in lectures and readings, then apply them in the development of a single program (requiring several months). We recently taught a software engineering class that incorporated many smaller exercises (requiring several hours). The class was successful: students were able to experiment with a broad set of ideas, and make interesting mistakes without jeopardizing the grades of their development team. This paper describes some tools and techniques we taught, and suggests how they might be incorporated into typical software engineering classes.