This paper considers different forms of classroom interaction, focusing particularly on cooperation, the different forms of cooperation, and the functionality of these forms with regard to learning opportunities. The form of student cooperation evaluated is defined as help. The research context is Gotz Krummheuer's project on the reconstruction of formats of collective argumentation in primary mathematics classrooms. The current work widens and complements Krummheuer's perspective by asking in what kind of cooperative situations one can expect processes of arguing. Data were derived from a project in Berlin, Germany. All classroom activities of a first-grade class were videotaped over a 2-week period in which field notes were taken and students' papers were collected. Three interactions were selected for analysis to show where student help becomes obstructive. Results illustrate aspects of help that can function in an obstructive way. For example, one partner may utter a wish for help which can function as a distraction. Further, one partner may help without being asked which can function as a nuisance. Contrastive analyses of less fruitful processes of helping along with describing arguing processes might help in developing the empirical basis for a grounded theory on the social conditions of learning in classrooms. Contains 13 references. (PVD)