At 11, your son should still be able to catch the obvious and subtle differences between the French and English phonemes, but it becomes increasingly difficult with age, unless if has a musical ear. Does he play a musical instrument?

I suppose you live in an English speaking country and his French teacher is probably not a native speaker. It would help to make him hear native speakers, both male and female. You could try audio books, French series, movies or cartoons on the Internet.

I have had the same problem with my own son who has been living in the USA for most of his life: he was mixing the different ways to pronounce the French R. I had to repeatedly make him hear the difference between crier and griller and how the French distinguish one from the other not because of the initial consonant but because of how it changes the way we pronounce the R that follows.

Listen and repeat, correct, hear the difference and repeat again...

At 11, your son should still be able to catch the obvious and subtle differences between the French and English phonemes, but it becomes increasingly difficult with age, unless he has a musical ear (en français l'oreille musicale). Does he play a musical instrument?

I suppose you live in an English speaking country and his French teacher is probably not a native speaker. It would help to make him hear native speakers, both male and female. You could try audio books, French TV series, movies or cartoons on the Internet.

I have had the same problem with my own son who has been living in the USA for most of his life: he was mixing the different ways to pronounce the French R. I had to repeatedly make him hear the difference between crier and griller and how the French distinguish one from the other not because of the initial consonant but because of how it changes the way we pronounce the R that follows.

Listen and repeat, correct, hear the difference and repeat again...