In the school district I grew up in (long before IEPs), students lose the protection of having an IEP when they leave middle school. There are no magnet schools. There are two big urban high schools and a couple of smaller ones; AP course availability varies from school to school and year to year (depending on faculty/funding/facilities availability.) You have the choice of enrolling in any high school that has space, but you have to provide your own transportation. This flexibility allows the district to claim that they meet the state mandate for gifted education. It is a largely-urban district in a depressed and depopulated industrial region.
I haven't lived there in a long time, but an old friend that I grew up with got her HG daughter through that system to graduation just a couple of years ago, and I witnessed the process starting with her middle school years.
My multi-racial nephew grew up in that district (he's now in his mid-20s) and since I'd promised many years before to support his education as fully as possible, I was involved in it from the beginning. We could not get him evaluated for the state-mandated gifted program (pull-out.) So, no IEP. He finished fifth grade at the top of his class, still no evaluation--the school (teachers and principal) stonewalled the family the whole way. Finances back then prevented engaging private testing, and anyway there was a history of the district not accepting private test results. Achievement test scores were in the high 90s. I thought he might have ADD but his scores and grades were so good that the school did not evaluate for that, either. All the schools he attended were inner-city schools, underfunded.
His middle school years were painful, and high school was a disaster. He finished his final year of high school in a special program for at-risk kids, at a local public university. He stayed at that university (a HBCU) for college, finally getting his ADD and depression diagnosed and addressed. Now, after alternating years of school with years of working, he's pretty much caught up with himself and will graduate with a B.S. soon.