Originally Posted by 22B
I'm trying to understand how and why "elite" colleges (not necessarily just Ivies) select students to admit using not just academics, but also "Extra-Curriculars" (ECs).

An important reason for "holistic admissions" is to provide cover for a process that sets racial targets for which kinds of students are admitted, even though explicit racial quotas are unpopular and illegal. A recent NYT article discusses this:

Confessions of an Application Reader
Lifting the Veil on the Holistic Process at the University of California, Berkeley
August 1, 2013

A HIGHLY qualified student, with a 3.95 unweighted grade point average and 2300 on the SAT, was not among the top-ranked engineering applicants to the University of California, Berkeley. He had perfect 800s on his subject tests in math and chemistry, a score of 5 on five Advanced Placement exams, musical talent and, in one of two personal statements, had written a loving tribute to his parents, who had emigrated from India.

Why was he not top-ranked by the “world’s premier public university,” as Berkeley calls itself? Perhaps others had perfect grades and scores? They did indeed. Were they ranked higher? Not necessarily. What kind of student was ranked higher? Every case is different.

The reason our budding engineer was a 2 on a 1-to-5 scale (1 being highest) has to do with Berkeley’s holistic, or comprehensive, review, an admissions policy adopted by most selective colleges and universities. In holistic review, institutions look beyond grades and scores to determine academic potential, drive and leadership abilities. Apparently, our Indian-American student needed more extracurricular activities and engineering awards to be ranked a 1.
Some commentary on this article is

Want to get into UC Berkeley? Lie
by Steve Sailer
August 2, 2013

Working in the dark
by Steve Hsu
August 2, 2013

The shell game of Berkeley’s holistic admissions
By Razib Khan
August 3, 2013

"To see what is in front of one's nose needs a constant struggle." - George Orwell