This contribution is a report on an intermediate linguistic seminar entitled Using Corpora for Writing Skills. Its overarching goal is to enable students to use corpora, (i. e. large computer-searchable text databases) independently, routinely, and confidently for a variety of purposes. Besides acquiring the basics of corpus research, they practise applications to different central topics of foreign language learning, such as prepositional choices, collocations, confusable homonyms and synonyms, register differences, grammar issues and varieties of English. Emphasis is placed on an appropriate evaluation of the results. Overall, the course received very positive feedback and the willingness of participants to use corpora was significantly higher at the end of each semester than at its beginning. However, what could be established as a major challenge is the fact that students tend to hold on to their binary judgements of right and wrong. Teacher education should thus foster a corpus skillset as a handy tool in everyday school life, along with an open mindset that involves acceptance of heterogeneous corpus data as fully legitimate variation.