any smart 12 year old could easily pass the GED
I taught adults and incarcerated juvenile delinquents trying to pass the GED many years ago. The test may well have changed since then, but for math, one big stumbling block was knowing how to deal with fractions. That was then considered a 5th-grade math skill (yes, I know this was a while back). At a high school math level they were supposed to be to calculate square roots using pencil and paper.
The GED was a hard test back then because it was supposed to show the student actually would have been able to graduate from a rigorous high school education. I have no idea of how hard it is now. There is also an alternative test to the GED, but I’ve been out of touch with Adult Education for some time.
Even if what you say is true you still haven't convincingly refuted my statement about kids attending the schools of major cities.