[watwut]

Colleges are also full of students from public schools. America has plenty of good public schools (but also bad ones). America tend to be country of large differences and it shows in school results too.

Homeschooling parents love to use worst poorest least performing public school as a norm and best performing home schooled students as a norm.

[analog31]

Definitely true. And I have to disclose that my familiarity with homeschool kids is biased: They are all drawn from a particular demographic (educated parents) and from a particular activity (classical music), because my kids happen to participate in that activity as well.