There is no single US. Each state has it own program to separate students into different tracks. In mine they identified "talented kids" in 3rd grade and they h

There is no single US. Each state has it own program to separate students into different tracks. In mine they identified "talented kids" in 3rd grade and they have advanced math and language programs going forward. They had additional evaluations in middle and high schools. So it wasn't like all doors are closed after the 3rd grade. Regular public schools in a pretty big district that combines both urban and suburban schools.