This work presents a longitudinal didactic experiment based on the idea that literature, especially fiction, can serve as a basis for developing competence. Of critical importance is the teacher’s knowledge of the variation of conceptual depth in teaching materials. Based on five empirically discovered degrees of difficulty in literary texts, examples of writers and novels suitable as teaching materials for each degree are discussed. Further, a three-year authentic program in the subject of Swedish at the high school level is presented, whose sequential order is offered in the form of modules together with didactic reasons. Embedded in the regular lesson plan are five test occasions during the three school years. One student, who originally was diagnosed as low-performing, has been followed and the end result, graphically displayed in the shape of energy landscapes, points at progress in the development. The outcome could be taken as evidence that governance through the text materials has been successful.