I'm not disagreeing with you per sé, but it is possible that some crucial stuff is learned in the 15 years before these tests were administered? The reason I'm

I'm not disagreeing with you per sé, but it is possible that some crucial stuff is learned in the 15 years before these tests were administered? The reason I'm asking is that purely based on a 'hunch', I feel that the most useful years of my education were before the age of around 12-13 and after the age of 20. I have no solid evidence to support this, just my experience and that of my peers. Edit: to try and support my hunch: in my country 12-13 is the age where the 'sorting hat' is applied and you move to middle/high school (physically different location, on of three levels based on earlier performance), and 20 is generally around the second or third year of 'higher vocational training' or 'university' where the non-motivated are sorted out and (generally) the ones who are going to finish college are left. It's also the point where classes become less general, multiple-choice, massive (300+ classes sometimes) and instead become more focused and interesting.