The question of whether English or French school children learn better
how to write their own language probably comes down to the question of
pedagogical method and, even more, of what the school system thinks is
important. As a colleague of mine who is from Mexico says, "You never
learn to write the accent marks unless you get a ruler across your
knuckles in the third grade." I've made a linguistic analysis of the
relationship between Spanish pronunciation and Spanish spelling, and
some of the "spelling" rules, i.e. how to get from pronunciation to
writing, are of the form 'if neither A nor B, then do C, otherwise do
D'. It's the kind of backwards-feeling rule that is frustrating to say,
altho one can put it into logical calculus or a computer easily enough.
So I believe him about learning to write accent marks. Also, (purely
anecdotal evidence from years of hanging around returned missionaries),
I've gotten the idea that, for some indigenous languages that are
written with diacritic marks, the indigenee students who have
French-speaking teachers learn to write the diacritics, and those who
have English-speaking teachers don't. Apparently, the French speakers
take diacritics very seriously and make sure that their students learn
to write them in their own language, while the English speakers figure
that "those little fly-specks don't really count", and don't drill their
student on writing them. Just a suggestion.