Today a competent selection, evaluation, use and reflection of information is an important condition of social participation of children and adolescents. However, in both empirical and theoretical terms there is the need for a corresponding model of Information Literacy. Taking up this desideratum, goals of the dissertation are a theory-driven development and empirical verification of a model for Information Literacy of pupils and the development and testing of a standardized instrument for measuring Information Literacy. On a theoretical level an action model of Information Literacy is developed which is the basis for the measurement of Information Literacy. Considering this competence structure model, a standardized instrument for measuring Information Literacy is developed. Based on an empirically derived first data, this instrument is evaluated, the model of Information Literacy is validated and didactic instructions are derived. In addition to this empirical approach, in theoretical terms especially the relationship between Information Literacy and Media Literacy is analyzed and clarified.All in all, the dissertation contributes to research on Information Literacy and Media Literacy:In particular, the development of a standardized instrument for measuring Information Literacy is novelty in this research area. Using this model, an intervention for the promotion of Information Literacy (in schools) can be developed in order to close a gap in the media education- and classroom research.