I was in Mississippi public schools
1963-1970
French elementary
Hardy Jr high till forced busing Christmas break 1969 imposed by courts
We were taught phonics
In schools in general, no.
It was not implemented everywhere all at once. But it did start in the 1930s. Actually a bit before but at that point it became a policy being pushed. The further out in the sticks you were or the more stubborn your school board/principle the later it arrived but arrive it did. By the mid seventies it had completely saturated the public education system.