Knowing "what do I know" and thinking about "how do I learn", that is metacognition, is an important element in learning. The Finnish curriculum points out metacognition in the choice of the studying methods. The methods should help the students to become aware of their own learning, to develop better learning strategies, and skills to apply the strategies in new situations. In this qualitative case study the metacognition of Finnish sixth graders (N = 19) was studied in a virtual learning environment, ENO--Environmental Online. Pupils' metacognitive knowledge and skills were studied in one ENO course. The aim was to describe what and how pupils monitor in their learning processes. It was found that 11-year-old sixth graders possessed declarative and procedural metacognition, and also some conditional metacognition. In this study, the social component of learning was especially emphasized. (Contains 4 tables.)