Oh sure Q, I also knew things and songs my parents didn't think I knew and I suppose that's the case for a very big lot of people. But they weren't taught to me by my teacher(s), and as a teacher, I never taught them at school either. As for songs, I never taught my students "Jeanneton prend sa faucille larirette..." (usually the first naughty song kids learn) -though the lyrics are pretty innocent compared to Jean-François de Nantes, but I would sing "Sur la route de Dijon" to them until I finally realized what the whole battalion consoling Marjolaine really meant as the advice "Si vous passez par Dijon, allez boire à la fontaine" follows. Nobody ever complained I did but maybe the kids never mentioned it.