I concur. I went to a very wealthy public high school where there were multiple "tracks" one could be in mathematics. Your placement in one of these "tracks" depended on the teacher's recommendations from 6-8th grade. I did no homework, never raised my hand, never studied and still pulled down B+ averages through innate ability. Frankly, I was bored by the material. I was placed in lower tracks by the teachers. Meanwhile these girls who tested at C levels but stayed after school every day, kissed ass had tutors bought by their parents were placed in the advanced tracks.
To this day I am extremely biter about the outcome. I had to take extra courses and summer classes to get myself back into the AP tracks in high school. I went on to graduate with honors in mathematics and received a PhD in Computer Science. I imagine the girls who struggled with 6th grade mathematics material aren't still in technical fields but hey, they were the ones who "worked hard" and accepted the system so they got accelerated.