This paper examines the ways that intentions are formed in classroom interaction. The setting is an English lesson at a maritime institute, and the topic is the grounding of a freighter. The formation of intentions is seen as an interaction phenomenon. A systematic approach is adapted on mental phenomena. In this approach psychological phenomena, including language use and intentionally, are seen as resulting from the interplay between man and his environment. The emergence of intentions on different levels of this interplay are explored. The levels range from face-to-face interaction to the interaction between the individual and the social structure. The impact of institutionalize in teacher behavior is emphasized, and the proposed frame of reference is illustrated by preliminary empirical findings. (Author/VWL)