You need to remember that public education has both national and state standards in the US, but that national standards can be ignored if that state simply decides not to accept federal money to help run their schools. This is SUPPOSED to be a gun to the head of the states to get them to agree to a unified curriculum (that has room to teach state relevant topics) but the wealthy donors have made for-profit schools their next pet project and are putting folks in office that are perfectly willing to just reject that funding. They -want- public schools to fail because their backers are running the charter and private schools that are the only alternative, which only retain their academic standards by only accepting students who can succeed. So now the gun is at the head of the federal government: they can ether put out a relevant, complete curriculum that will be rejected by bought politicians or they can put out this half-assed shit they've been doing since the 90's just ensure they can keep schools running, period.You americans are just screwed up. I remember fractions and factorization from grade 3.
And as for the marking, ENFORCING stupidity like above will absolutely screw over the student when it comes to things like algebra, where the name of the game is reorganizing variables. If they don't understand early on that both forms are the same, they're MORE screwed later, not less.
That's not even getting into the textbook and equipment issues that start in Texas because it has the largest school districts. Certain companies have defacto monopolies (like Texas Instruments) because of their political connections.
So yes, the education system is completely fucked in the US because some people think they can make a buck off of it, at the expense of the children.