Starting from the assumption on the importance of influence that school and family exert on child development, the paper analyzes the effects of parental treatments on child social behavior. Empirical evidence proves that parents who contribute to the fullest extent to their children’s successful adaptation to school conditions, possess a specific style of communication with their children: they consistently support just behavior standards encourage a two-way communication, respect child’s opinions, are highly expectant of child’s responsible and mature behavior and care about his physical and emotional well-being. However, there is relatively lesser empirical evidence of teacher contributions to child successful adaptation to school conditions. The findings of more recent studies on the problem indicate that adaptation of younger age children significantly correlates with the quality of relations established with teacher, characterized by warmness, conflict absence and frank communication. The possibility of solving the problems children encounter is found in cooperation of school and family. A child generalizes his experience of family interpersonal relations onto relations he will find himself in throughout his life. In addition to family, the classes where cooperative relations intensively develop are a favorable base for socio-emotional development. Democratic and cooperative climate contribute to stronger ties between students. Joint activities of teachers, parents and peers, in and out of the class, are of crucial importance for student optimal socio-emotional development.