A vital part of student learning is the construction of mental structures encompassing categories believed to affect learning outcome. In this study we investigate this research question through the lenses of a constructivist approach. As the first study on our research question at high school in Norway, our empirical findings make up the main contribution of this study. The data were analyzed by a grounded theory methodology. The results identify 6 dimensions of determinants of learning outcome. The dimensions: student activity, work processes and motivation to learn are manifest of the latent dimension process of learning, while the second latent dimension learning content is manifested in the 3 dimensions: correction, information from teacher and putting into context. (Contains 1 table and 2 figures.)