The adoption of educational standards for core subjects by the Conference of Ministers of Education in 2003 and 2004, along with the demand for individualized instruction, requires teachers to rethink their planning and design of teaching and learning processes. However, teaching does not change simply by redefining normative-political guidelines. It is equally necessary to support teachers in meeting these new requirements. Against this background, the federal state of Hamburg initiated a school experiment a few years ago, with the overarching goal of supporting teachers at the 48 participating general education schools in advancing competence-oriented curriculum development and, furthermore, developing and implementing adequate forms of competence measurement and description.