Coal in your Christmas stocking might be a reminder to straighten up and fly right for next time.
Look to the cartoons to teach ya. My Little Pony‘s Pop Fly laments show tune style with “Last Year I Got Coal for Christmas.” On the path to improvement, but that attitude needs adjusting still.
Private Eye Music go boogie woogie with their loaded lesson “Lump of Coal.” Kid took his lumps and came back reflectively. Or at least looking at how his behavior differed from the other children. Well, the song sure is fun.