This article describes the gathered experience in using corpora in an IELTS preparation course. The practice demonstrates an attempt to reduce negative washback effects occurring when preparation courses just concentrate on the test format neglecting the importance of development of learners' language skills and general study skills. Some corpus-based activities, which were used in a group of Russian university students for teaching vocabulary and writing, are provided. The author's experience in using corpora proves such positive effects of corpus teaching as an increase in the learners' understanding of usage patterns, drop in the number of collocation errors they make, enhancement of the students' autonomy and self-correction skills.