1) Perhaps SAT measures nothing more than literacy, but because college admissions uses the scores as a metric, the people who score high get to go to uni and meet people from wealthy families thus putting them on track to be wealthier, etc. This could occur regardless of what SAT measures.
2) How are these state-wide and nationwide scores calculated? Has the number of students taking the test gone up in certain populations of people who may have various reasons to score low? Perhaps as the test became more popular more and more schools began administering it. At a certain point only the lowest common denominator schools are left to join in.
#1- In short, yes, but generally by coincidence. A student's SAT scores generally correlate with their high school GPA and difficulty of taken classes, so, in most cases
, whatever the student's SAT scores show colleges and universities could be communicated just as well by their high school transcript.
#2- It's deviation from average, much like an IQ score. I can't remember the exact processes involved or score scaling, but it's adjusted annually to maintain a national norm. And you're right about your last few points, though I doubt anyone has a reason to NOT do well on the SAT.
From my personal experience the SAT shows little more than the basic education covered by grades 1-12. It's broken up into three sections, reading, math, and writing. Here's what each test entails:
Reading: How well you can interpret awkward passages, often excerpts from novels that have no background info given. Also includes knowing what various words mean. Unless you have a fifth grade reading level, you shouldn't get less than a 550.
Math: Basic math, with few problems more advanced than geometry. Definitely falls in the information regurgitation category.
Writing: This is a "personal" essay section, where you write about something you probably don't give a damn about. Colleges generally ignore this section unless a tiebreaker is needed.
The SAT says nothing about the student's character, giving only a vague rating of academic potential. nothing is said about their personality, history of mental health/stability, or leadership ability.
At the very best, this test separates college candidates into three groups; yes, maybe, and hellz-to-the-no. Sure, it's useful, but the student's transcript and references ought to do the same thing.