> I don't understand. US high school kids only do math one year out of the 4? And nothing else math related during the other 3 years? No, he/she meant that US

> I don't understand. US high school kids only do math one year out of the 4? And nothing else math related during the other 3 years? No, he/she meant that US high schools divide Math into algebra, geometry, trig etc. which are taught in different years as opposed to simply having these as sections in a single Math textbook which increases in difficulty every year. High school is too early to divide up Math into these subjects especially if you are going to be studying only one of these in a whole year.