1) Differentiated instruction is done pretty much across the board and has been for years. 20 years ago, my crap district had an advanced reading group and a lesser reading group. You're telling me this isn't going on at your schools?
2) Does your district have honors classes? Not even in junior high? Again, when I was growing up, this existed in elementary school AND junior high and my school district wasn't great.
Congrats on being a parent. Will you hire a tutor like other parents do too?
No honors classes in junior high, but now your daughter is suddenly in AP Calc as a freshmen? As a counselor, I would love for you to share the 'Advanced Math Track' for your high school.
Either your daughter is a genius or you're full of crap.
Based on these paragraphs, you may have done a poor job of locating a home within a good school district. Any decently funded district would have everything you're asking for. Any blame on yourself here? Never looked into it, and never moved?