You must have attended a private or EXTREMELY large school. Most US schools are nowhere near the described Netherlands system. At best, you've got three tracks - "honors" which targets the cookie-cutter wrote memory college tracked kids, standard for those who aren't fighting or don't care about math scores WRT university applications, and "essentials" for poor suffering masses who are not picking up or don't care to do the work. This is the situation in Washington State, Kent School district which is the 4th largest district in a High School with over 2600 students. Even this delineation of "skill" is still cranked through the un-inspired compulsory process Lockhart complains about. If you want to know why, check out John Taylor Gatto's "The Underground History of American Education" (http://www.johntaylorgatto.com/underground/).
Saying knowledge comes from a schooling about as correct as saying milk comes from a store. When you understand in both cases it's just simple packaging and processing, you can start asking questions about what it is, why it is, and how you can get it on your own, and how to evaluate the quality of the sources you get it from.