Background: The purpose of this research is to analyze the perception of teachers and their thinking about two specific and functional issues which are often deemed to be controversial, that is, the acquisition, by recently arrived migrant students of the host language and the role that the professional services of a cultural mediator may have in said school context. The methodology used has been a case study by means of the technique of in-depth interview. To this end, twelve teachers from an Italian comprehensive school in the region of Sicily who for several years have been immersed in the relatively abrupt arrival of immigrant students have been interviewed. Results: There is evidence of some teachers adopting the position from a classic epistemological approach in the field of interculturality. For example, while the attitude and involvement of teachers seems to be consolidated, the teachers think that a key element of real inclusion should include practical measures such as early immersion in the host language, in this case Italian, and that considerable and external professional efforts are necessary, particularly from cultural mediators, which could make the inclusive project more viable.