Automatic tools for analyzing student online discussions are highly desirable for better assistance and scaffolding. This paper presents an approach for automatically identifying student discussions with unresolved issues or unanswered questions. We apply a two-phase classification algorithm. First, we classify “speech acts” of individual messages to identify the roles that the messages play, such as question, answer, issue raising, or acknowledgement. We then use the resulting speech acts as features for identifying discussion threads with unresolved issues or unanswered questions using. We performed a preliminary analysis of the classifiers and achieved average 78% accuracy. Keywords. On-line discussion board, speech acts, discussion assessment