The way people interact with knowledge has changed tremendously for today's society, in that the skills of information-management are required more than those for the retention of knowledge. This "knowledge society" (Ruschoff, in Mibler & Multhaup, 1999, p. 80) thus greatly supports the implementation of technology in the education sector due to its capacities in storage, retrieval and communication of information. Yet this solution is not a straightforward one, since the merits of pedagogical tools need to be investigated first (Chapelle, 1998). The Chemnitz Internet Grammar (CING) is a web-based English grammar learning tool with an extensive body of authentic English language examples. To the researcher's knowledge no self-instruction tool with such a diversity of authentic English grammar material as that of the Chemnitz Internet Grammar exists. With its inductive-deductive presentation of content, various tools (Corpus Search Engine, Learning-strategy Test, Placement Test) the CING offers more than most instructional programmes. "Researchers and teachers do not have a clear conception of a task unless they observe how the task actually turns out during instruction" (Chapelle, 1998, p. 28). The CING faces a similar dilemma as using it is a task in itself, which is why its usability needs to be evaluated, to ensure its future success with learners (Preece, 2000). This evaluation shall contribute to an understanding of learners' experience with the tool's tasks and how the CING's usability is supported or needs to be improved. It is hoped to be a contribution to questionnaire design and evaluation in current CALL research. The results of more than 60 evaluation questionnaires on usability and content difficulty were collected over a period of three months. They indicate the kinds of problems users have with the CING and their positive learning experience. The group of subjects consisted of more than 60 students between terms one and seven, studying at the Univean intermediate 3 level of English grammar or higher. Questionnaires were filled in by CING users after self-guided learning sessions with the Internet Grammar.