Study of inter-ethnic friendships and social relations of primary school pupils related to ethnic perception of teachers and nature of school curriculum. P0904A: teachers on ethnic perception and curriculum offered / contacts with members of ethnic minorities / acceptance of cultural and ethnic differences / acculturation / stereotypes / knowledge of culture of minority groups / sympathy with minority organizations / attention in teaching for cultural differences / stimulation of positive attitude towards own culture / stimulation of inter-ethnic contacts / fighting stereotypes / using ethnic minorities, their culture and social position as teaching subject / stimulation of participation by parents of minority groups. P0904B: pupils sociometric data / friendships / playing / help relations ( both self-scored and teacher-scored ). P0904C: class typology / ethnic / cultural composition / sex distribution. P0904D: grouped frequencies and indices of sociometric data. Background variables: basic characteristics/ education