It’s not the school system, its the people who run the school system. Here in Valdez, a kid gifted in math can proceed at his or her appropriate level. For example, I have an 8th grader in college algebra earning college credit. I had him in 6th grade for geometry and 7th grade for Algebra II (this is my 22nd year of teaching high school mathematics).
what I would suggest is to have the person get singapore math books. Or start the kid on algebra. Math is pretty sequential in terms of the topics and difficulty. If this young lady has the maturity for math I suspect she does, then jumping her into algebra should not be a problem.
School districts resist placing kids in higher level math classes because it makes them uncomfortable. Its a bother and a pain to rearrange schedules, etc. Of course, their job is to teach _all_ the kids, but they think that applies to only kids at the bottom.
Another possibility is to find a sympathetic math teacher or two in the school district and see if they can help out. An experienced math teacher should be delighted to have a bright and energetic student in their class.
“get singapore math books”
If these are basically the same as the Chinese Math books my wife used, this is a great tip. My girl is an 18 year old college junior, studying Chemical and Bio-medical engineering. She’s still way ahead of the others in her classes, and it’s due to her Mom’s tutoring in Chinese math. Well,,, and her own ability and determination...... I never understood a word of what was going on, as it was all in Mandarin, but I’ve seen the results, and they’re impressive!