Switzerland, like other countries in Europe, has long depended on migration and mobility for its economy. Facilitating the integration of migrant children in school, primarily through the acquisition of the local language, has therefore been a priority for policymakers. In recent years, mobility has been on the increase and mobility trajectories have become more diverse. A growing percentage of families arriving in the country have experienced repeated mobility and may not plan to settle in Switzerland for good. This paper examines institutional responses to the increasing number of mobile children in Swiss public schools, in particular, the manner in which such children are welcomed. It presents the main findings of an exploratory research project focused on children in repeated mobility, defined as having lived in multiple countries before their arrival in Switzerland, regardless of family background or legal status. Adopting a sociocultural psychological approach, the paper examines the macro-social level of cantonal educational policies regarding welcome processes, the meso-social level of local school policies, and the microsocial level of teachers’ practices and interactions in classrooms that welcome mobile children. Data include documentary analysis, interviews, and observations. Our analysis shows that a deficit view of mobile children and the preoccupation with language proficiency dominate policies and practices, resulting in the diversion of mobile children into special integration classes (so called “classes d’accueil” in the French speaking region, and “Integrationsklasse” in the Swiss German-speaking region). Mobility is conceptualized by Swiss policymakers, school directors, and teachers in terms of its challenges. In particular, school directors and teachers conceptualize mobility as increasing heterogeneity of the classroom. However, the situation varies greatly according to the personal orientations of school directors and teachers’ personal engagement. The paper emphasizes the ambiguous role of the integration classes: while they may impair the long-term chances of educational success by reducing academic expectations for non-native-speaking mobile children, they may also be used as “third spaces” which afford pedagogical freedom for dedicated teachers, potentially of benefit for children. The paper examines these propositions in the light of sociocultural educational literature and draws upon the case of welcoming mobile children to question a series of assumptions about the ultimate purposes of public schooling in Europe today.