How wonderful!
My DD and I are both working on manners for DGS. He is speech delayed and mildly autistic so it is a bit more of a chore, but most times he will be polite if reminded (what do you say). Unfortunately the school is not reinforcing the please and thank you, just settling for yes and no.
My friend's DD was told her elementary school child was "too polite" and that the teacher found it irritating! Wonder why the child didn't like school. . .