My child recently learned this in school, in first grade. I just assume everyone knows it. There's an English jingle that I was taught (1970s), and my child a

My child recently learned this in school, in first grade. I just assume everyone knows it. There's an English jingle that I was taught (1970s), and my child also: Thirty days hath September, April, June and November. All the rest have thirty one, save February alone Which has twenty eight days clear, and twenty nine each leap year. (ok, the "hath" part was what I was taught, I think he learned "has" :-) (edit: in Australia, for reference)