Perhaps this picture can explain why the Bais Yaakov’s don’t want Sephardic girls in their schools?
Ynet:

Each year, as the school year begins, hundreds of cases of sweet little girls � whose only “crime” is being of Sephardi background �are forced to remain home after being rejected by the ultra-Orthodox Beis Yaakov school system. School principals admit openly that they reject student’s because of their ethnic backgrounds. A legal ruling, the first of its kind, issued by the Jerusalem District Court, has now given legal teeth to a phenomenon we have observed for a long time: “There is a suspicion that registration procedures employ ethic criteria in their admission standards.”The quota system by which schools limit Sephardi registration to just 30 percent of the total student population is both well known and deeply rooted. When a student is accepted to a Beis Yaakov school, the principal is expected to mark down whether the student comes from an Ashkenazi or Sephardi family. These principals � who come from the haredi (ultra-Orthodox) stream associated with Rabbi Yosef Shalom Eliashiv, and for whom the principles of democracy are not exactly an area of expertise � see nothing wrong with this openly racist practice. After all, the Beis Yaakov system was originally established to serve the needs of Ashkenazi girls………..