<em>If a kid goes to Troy Tech ( A magnet school in Fullerton ranked in Top 25 in USA), does his chances of landing in any ivy league or a USC/UCLA increase?
</em>First of all, I'm assuming that you are referring to Troy's Magnet Program, which as far as I know is distinct from their "regular" public school program (kids who are fed into the school based on their location). Your kid will have to pass an admissions test administered in December to get into the Magnet Program. For more information see here: <a href="http://www.publicschoolreview.com/school_ov/school_id/7490">http://www.publicschoolreview.com/school_ov/school_id/7490</a>
If you assume that all kids are equal (in brainpower, special extracurricular talents, ability to market oneself in the application process, legacy-donor status/connections), then yes, going to a magnet high school appears to increase their chances of matriculating to an "elite" college. After all, Troy, Whitney, and private boarding schools like Harvard-Westlake and Phillips Exeter send a higher proportion of their students to those "elite" institutions. But, that would be a pretty preposterous assumption wouldn't it?
<strong>Don't mistake correlation for causation here</strong>. Going to Troy is not a guarantee that your kid will be going to Stanford. See <a href="http://daily.stanford.edu/article/2007/5/24/imposterCaught">Azia Kim</a>, who after graduating from Troy, attended Stanford for a year - despite the tiny problem that she was never admitted in the first place. It is a testament to the academic pressures that she faced at Troy and from her family that she had to construct an alternate reality of herself - one that gained admission to Stanford - in order to impress her family and friends. For students similar to Azia, who are not smart enough or cannot handle the increased pressures, I would argue that going to Troy could minimize their potential for matriculating to an "elite" college because their confidence is undermined.
In my opinion, the reason why Troy or Uni sends more students to those colleges is because their student body has a high proportion of Asian students who come from demanding families who place an emphasis on academics. Each of those schools have a plurality of Asian students. For magnet schools like Troy and Whitney, they actively select for students that have great academic potential by administering an admissions test. On this basis alone you cannot compare the "quality" of the high schools without talking about the inherent "quality" of the student body.
You can make an argument for sending your kid to a magnet school or another highly competitive public high school if you know for certain that your kid thrives in competitive environments and is motivated by their peers constantly playing the game of academic one-upsmanship. Most (if not all) parents cannot objectively look at their kids and determine if they have the goods to succeed in a competitive environment. After all, our kids are a reflection of our own genes. We all would like to think that our kids have the brainpower and talent to do this. Unfortunately, this isn't the case.
<em>If the same kid goes to Irvine High and does very well with APs, P-SAT and SAT, is he going to be at a disadvantage compared to kids who graduate from a magnet school like Troy Tech ( or Uni High)?
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If you take Student A who goes to Uni/Troy with 1500 SATs (old scale), 4.0 GPA, and Student B, who goes to Irvine with 1500 SATs, 4.0 GPA, it's an academic tie. It'll come down to their extracurricular activities, accomplishments, and ability to market themselves on their application to break the tie. If Troy offers after-school activities that would result in your kid having said accomplishments, it would help, but then again it's up to your kid to take advantage of those things.
<a href="http://forums.irvinehousingblog.com/discussion/1909/zip-codes-92618-92620-92603/#Item_10">"It ain't the school. It's your kid."</a>