It's also not an automatic thing, so a parent will have to be informed about the program and have the time to fill out the paperwork, and these schools are also at specific location, so if you live far away you might not be able to get there without difficulty and stress.
All of this puts filters on who gets to go, rather than just making space for everyone who shows interest in certain areas and puts forth effort. It also removes successful students from local schools, the proportion of academically inclined peers goes down, the proportion of bad influences goes up, and the entire school system suffers as a consequence. Ideally these programs should exist in house, expanded or contracted to fit the number of kids scoring >x% on whatever measure.
1. http://echoices.lausd.net/Magnet/MagnetGiftedCriteria
2. https://www.latimes.com/projects/la-me-edu-magnet-test-score...
To get into the highly gifted magnet, you have to request a subsequent test, which the district administers. You have to score above the 99.5 percentile.
I am absolutely certain nothing like this was available to any kid in my schools growing up.