In this project, the question of how social contacts affect the educational success and the apprenticeship search of students with and without a migration background was investigated. Both the social and ethnic network composition of the students and their mothers were taken into consideration. In order to theoretically approach the question, which effects social networks should have on the structural success of actors, the concept of social capital was utilized. Concerning the potential effect of the ethnic composition of migrant networks, well-established assimilation theories were evaluated, and a connection between them and the social capital concept was established.For the empirical analyses, data from the project „Immigrant children and youths in the German and Israeli educational systems” were used. It was shown that both the social as well as the migrant-specific network composition has an effect on educational success, whereby the influence results through different mechanisms. Concerning the social network composition, the results suggest that it has less of an effect on student performance, but rather on their motivation as well as on educational aspirations and educational decisions. In contrast, migrant networks which primarily contain individuals belonging to one’s own ethnic group, respectively, in which the language of the country of origin is primarily spoken, have a negative impact on the academic performance of the students, whereas, the educational aspirations and decisions are not substantially affected. The analyses indicate that educational inequalities are partly due to actors’ differing social capital endowment. These results apply at large to both the networks of the students and the networks of their mothers. In contrast, only the mothers’ networks have an impact on the apprenticeship search success, whereby the volume and social composition of the networks is of central importance. The adolescents themselves do not seem to have substantially useful social contacts in regards to finding an apprenticeship.Overall, a comprehensive overview of the impact of the different characteristics of the students’ and mothers’ networks on the different determinants of educational success and the transition into the apprenticeship system could be obtained in the project."