Why is the American high school system lagging behind other countries, but America has such brilliant universities?
Here I found some very interesting article (question and answers) about this issue.
I wrote about this elsewhere (Ben Waggoner's answer to How is the USA the most technologically advanced country when it has one of the worst educational systems?), but it bears repeating. . .
There is no such thing as “the American high school system.” It doesn’t exist. No existe. N’existe pas. So etwas gibt es nicht. Не существует. यह मौजूद नहीं है. فإنه لا وجود لها. 它不存在。
There are thousands of American high school systems.
Individual states set their own standards for teacher training, certification, and continuing education (training that teachers receive throughout their careers). States also generally set standards the curriculum—what subjects will be required and for how many years of study, what textbooks will be used, etc.—and administer standardized tests to determine how schools are doing. And local school districts actually build the buildings, set teacher salaries, hire the teachers, and fund most of what the school does on a day-to-day basis. The US Department of Education does whatever it does (or doesn’t, now that DeVos is in charge), but it can’t actually impose a national curriculum.
What that means is that American high schools can vary dramatically in quality from one state to another, and from one district to another. On one test given to high schoolers around the world, PISA (Program for International Student Assessment), the US ranked 21st in reading and 31st in math. But if states could be ranked independently, Massachusetts would rank 4th in the world in reading and 9th in the world in math. On the other hand, Mississippi would be somewhere around 40th place in the world, alongside Uruguay and Trinidad and Tobago; and the District of Columbia would be somewhere near 45th place, fighting it out with Albania.
(Source: If Massachusetts Were A Country, Its Students Would Rank 9th In The World) https://www.forbes.com/sites/jamesmarshallcrotty/2014/09/29/if-massachus...
And within low-ranking states, you can still find excellent districts and excellent schools—and of course, you can find poor districts and poor schools within high-ranking states. Not every Massachusetts high school is on par with Boston Latin School or John D. O'Bryant School of Mathematics & Science. In most areas, the school you attend is determined by where you live, and a family with children will often pay a higher price, or purchase a smaller house, in order to live near a good school. (Good schools increase surrounding house prices)
The point of all of this is that American high schools vary—from globally elite, to bombed-out ruins. But there are enough excellent districts and schools that the top American universities can select the best. And life being what it is, there are even excellent students in “bad” high schools—my wife taught for a while in a small rural high school with high levels of poverty and drug abuse, one that would never be thought of as “elite”, and yet one of her students was being headhunted by Harvard.
As for why this disparity exists. . . that’s a controversial question, and one that’s been argued for a long time. But clearly some of our high schools are doing everything right.