The reason that public schools wallow in mediocrity is the following imo. The informal primary mission of public schools in the USA is to babysit kids for working parents, parents who don’t have enough energy at the end of the day to fight the indoctrination that their kids are getting from the public schools.
How to fix problem.
End Federal Gov. involvement in schools! Put control back in hands of the states. Go over the teaching guides and purge all the BS.
Teach what kids really need to know as citizens. Like how to do taxes and fill out an appilcation. And English.
Break the back of the Teaching Unions.