The aim of this cross-sectional study was to describe the social skills that crucially affect children's social behaviour in the school. Our objective was to gather information about the functioning of social skills from middle childhood to early adolescence. The sample consisted of 7-, 9-, and 11-year-old Hungarian students (N = 1398). Based on Stephens's (1992) list of social skills, a 54-item Likert-type questionnaire (teacher-, parent-, and self-report versions) was developed especially for this purpose. The child and the adult versions share the same structure and scale items. The results show no spontaneous development at the level of social skills between the ages of 7 and 11. There was a moderate correlation between the three evaluators' judgements concerning the level of children's social skills. All three respondent groups indicated that girls' social skills were slightly more developed than boys'. Teachers, however, perceived this difference to be twice as large as the other two raters. To sum up our results indicate that for a large percentage of participants, the acquisition of social skills has not been completed at 11 years old. This finding indicates that more attention should be paid to fostering social skills early at school.