Videotaped group work lessons of an elementary school third grade class provide material for study of the non-verbal aspect of group behavior. A system of activity categories is developed and a typology of pupils' working methods in group study distinguishes types and characteristic forms of activity. The following activity categories are used in the case study: (1) Independent activity on own initiative, (2) Collaboration, (3) Helpful activity, (4) Attention to task, (5) Search for knowledge, (6) Passive activity, and (7) Disturbed activity. Five dimensions which reflect a working type are noted: Independent, Solidarity, Work-centered, Passive, and Disturbed. Results of the study are analyzed and presented in graphic form. It is found that the development of categories succeeded in terms of reliability and non-ambiguity, although validity was not established. (SHM)