Is there any chance that the school was reluctant to allow her to take some of the honors courses as a URM? I don’t like to borrow trouble. It might just be ordinary gatekeeping at the school since you said that they limit honors classes in general. However, with one of my URM daughters, I had to push very hard to get her middle school to let her take the accelerated 7th/8th math course. The school was going to put her in the regular Algebra 1 and it took a lot of back and forth with her 6th grade math teacher and insistence on my part to get her placed in the higher track --she did very well as I knew she would.
Different school, but my rising senior at a private school asked the math department if she could take a math class this summer and then a placement test in August because she wanted to take Cal BC her senior year. Right now, she is signed up to double in math with Cal AB + the school’s equivalent of AP Stats. She was denied permission to take the placement exam at the end of the summer, which is fine, but she claims the school has routinely allowed her (non-URM) friends pursue outside classes or outside tutoring during the summer (and even during academic year) in order to take the appropriate placement test for the next level course. Note this is a kid who has gotten all As in her math courses at the school and hit the 99th percentile on her math SAT (and received “grand honors” when she took the Johns Hopkins CTY tests though the school doesn’t know this). While I pushed for her older sister’s middle school, I told her to let go of the summer math course idea given she is already plenty busy in July and August.
But I will always sort of wonder if there was some bias involved with both girls especially my rising senior (assuming she is correct and some friends asked the same question and were told go for it by the math department).