Мы говорим о том что из частных школ "первых" больше чем "последних". Вот к примеру кусочек. " A Brief Portrait, the U.S. Department of Education had this to say about the academic performance of private schools:•Private school students generally perform higher than their public school counterparts on standardized achievement tests.•Private high schools typically have more demanding graduation requirements than do public high schools.•Private school graduates are more likely than their peers from public schools to have completed advanced-level courses in three academic subject areas (see table).Private school students scored well above the national average in the National Assessment of Educational Progress (NAEP). NAEP scores provide an immediate measure of student achievement, but the report also presents a long-term measure: attainment of a college degree. "[S]tudents who had attended private school were twice as likely as those who had attended public school to have completed a bachelor's or higher degree by their mid-20s.A Harvard University study (pdf) challenged the results, using the same data but different methods. Researchers found that private schools came out ahead in 11 out of 12 comparisons of students."