I have been Catholic all of my life and I come from a long line of Catholics, been to Churches all over the world and have NEVER heard of Sunday school for Catholics....NEVER.
Well, we always used the term “Sunday School” for those religious education classes for public school children, generally scheduled for after the children’s Mass. Granted, for the past 20 or 30 years, the church bulletin refers to it as CCD. I still say “Sunday School” — that’s what it was when I went, and that’s what I called it when I taught it.