When everything is based on "one exam", presumably for all the colleges in the country, who determines what that exam is? I don't trust the federal government to do so.
The exams are very different overseas. First, no multiple choice. Second, students often get to choose the questions they want to answer; the paper may have 8 questions, and you only have to answer 5 (or whatever). The exams are graded by humans who are subject experts, using guidelines created by the examination commission (
here's an example from a recent mathematics exam in Ireland). If you look at that exam, you'll see that it's light years ahead of our SAT or AP exams in terms of what it measures and how it measures it.
There's typically a national curriculum and all students take the same exam. I understand that many Americans are used to the idea of local control, but this approach wastes a lot of money by repeating effort and doesn't guarantee quality anyway. A national curriculum is also transparent.
As far as I know (in Ireland and the UK anyway), the exams are written by subject experts (university academics, possibly teachers). I recall that my university tutor (in Ireland) wrote questions for the O or A levels (in the UK).
In predicting college grades, both high school grades and SAT/ACT scores matter. Why shouldn't high school grades count?
With respect, that's a very US-centric view of how things ought to be (and it's not backed up by evidence; I also think there are questions about the predictive value of the SAT. Not to mention the effects of grade inflation.). The goal of the overseas exams is to measure how well you learned the material overall, not how well you learned as it came, in small pieces.
Obviously, European students get grades every year, but as ColinsMum said so well, it's a mistake to use the same work for learning and summative assessment. What counts is eventual mastery, not the steps taken getting there. A parallel is athletic competitions. We don't pick Olympic competitors or medalists based on how well they did throughout the duration of their training. Nothing matters but the "test:" how fast you ran the 100 in the qualifier race, how good your axels looked, etc.
One thing about US schools that really bothers me is that the percent of correct problems on homework often counts toward final grades. Students aren't even allowed to make mistakes when they're learning! To me, that kind of constant pressure has got to be worse than one set of exams that you can repeat next year.
