I know you only said "well-off", not rich/entrepreneurial class. But given what I've seen on HN lately I feel this must be emphasized -- this is not another "blame the rich" scenario. This is beaurocract class/college-educated-but-barely-passed education master's degree class. This is a government/administrative bloat problem. This problem is one you're much more likely than not to hear an entrepreneurial class member rail against and maybe even try to fix (to no avail).
The article says that administrators are giving in to the demands of very involved, upper-middle class parents. What other incentives would an administrator have to keep low-income and minority students out of 8th grade algebra?
Just as an example,
"The enrollment process created additional barriers for students and families. When students went online to select their courses, in many school districts they could not see classes that required teacher recommendations and may not have known those courses existed. Students who requested placement in advanced classes were frequently told they could not enroll, even when they had strong academic credentials. Students had no pathway to demonstrate their readiness or earn their way into these courses through their academic performance. They had to be recommended by a teacher."
Maybe this system shouldn't be set up this way? Who set up the system I wonder.