Education for All is a challenge in educational research on many levels. One important research aim in that context is the collection and interpretation of longitudinal data in order to model students’ competencies and their development. One central aspect of educational success is the spelling competence of students. Along the lines of current results in large-scale reading studies, the spelling competence can also be interpreted as a differential competence The results of the 2001 supplementary study of PIRLS-Germany confirm a five-dimensional model of the spelling competence of the primary students. However, compared to findings obtained for students in primary education, research results obtained from older students point towards a reduction of the competence dimensions in question.

Following these results, the longitudinal collection and interpretation of spelling data is one major challenge of the research group focusing on secondary school in the National Educational Panel Study (NEPS). As systematic research regarding the development of spelling competencies of secondary students is missing, major questions have not yet been answered. Three of those will be focused on in this paper:

1. How can reliable tests be developed that allow a longitudinal anchoring and that account for individual demands in different grades and corresponding competence levels of students throughout secondary school?
2. Does the structure of spelling competences of students change over time and if so, in which way?
3. Can typical patterns of change be detected for students of different ability groups?

In order to answer those questions, data from the NEPS developmental studies from class five to seven will be used.

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