If you were the president of a prestigious university how would you decide who to offer admission to?  I think in an ideal world you would love to sit down with each applicant, take a look at their body of work, get to know them and then decide if they are a good match for your school. Now, back to reality.  You can expect up to 5 times the number of applications as you have slots so you have to have an efficient initial screening process that can immediately eliminate most of the applicants.  You basically have two choices when it comes to evaluating a high school student, their Grade Point Average and their S.A.T. scores.  So the question immediately arises, which do you weigh more, G.P.A. or S.A.T. scores?  Let's take a look at each of these:

G.P.A.:  Remember how you and I padded our GPA's with easy courses while thinking "How can an 'A' in ceramics count as much as an 'A' in Calculus?  We also justified it by saying "Everyone else is doing it so I have to just to keep up!"  Well the jig is up and nowadays only (legitimate) college prep courses count towards your college GPA so you don't have to worry about a student padding their GPA with ceramics classes.  

High Schools also level their courses differently nowadays.  When I went to high school there was regular math and "excellerated" math.  Both courses recieved the same number of points (4) for an "A" so I am not sure why I, or anyone for that matter took, "excellerated" math is beyond me.  Today, students can take "honors" or "Advanced Placement" courses which give them 5 points for an "A".  This results in some students leaving high school with a GPA well above 4.0.  

It's also very hard to guage how a harshly a school grades it's students.  Schools that grade on a curve may have signicantly different results than schools that do not.

S.A.T. scores:  I am not a huge fan of standardized testing but I am also not comfortable placing the entire decision on a student's GPA.  Since most decisions are made by the spring of a students senior year and the freshman year does not count, a student's GPA is based on 5 semesters of work.

Something depressing:  Students with learning disabilities are allowed extra time on the SAT and a few years ago someone noticed that half the kids taking the SAT at a swanky Santa Monica private school were diagnosed with learning disabilities and recieving extra time on the SAT.  Turns out that they did not have disabilities, what they had was access to a doctor willing to diagnose them so that they could recieve the extra time on the test.  Believe me, if they really had those disabilities they would have NEVER EVER gotten into that school!

Also, there are many SAT prep courses out there and unfortunately the really good ones are very expensive with unevens the playing field for many students who cannot afford the prep courses.

Other factors:  Forget letters of recommendation which anyone can either get or forge, forget personal essays which are useless and forget community participation (student government, athletics...), those factors are too easily fabricated.  These are fine to break ties between the last few students but I would not place too much emphasis on these.

I would weigh the applications with 66% of the decision stemming from the students GPA and 34% from their SAT score.  I would also give special priority to in-state students.

What would you do?