[thufry]

In the United States, most public education is administered at the town level. Because towns are so small compared to counties/states/nations, the variance among towns in parameters is very high -- two towns only 15 minutes apart can easily vary twentyfold along parameters like average income and percentage of adults with graduate degrees.

Thus, what passes for a "standard high school education" in the United States varies wildly -- in some schools, you can graduate without even being able to read and comprehend a magazine article. In others, the top graduates often find Harvard less intellectually rigorous than their high school (because Harvard has to help their students from worse high schools catch up).