Idioms & Expressions

One of my favorite things about children is how they make up their own expressions and mishear real ones.
M has coined the phrase "a freckle or a pimple" amount of something (often used when negotiating, i.e. "a pimple more of ice cream"), "rusty" (wilting) flowers and "spanking" hot water. I find these neologisms to be quite picturesque and effective in the images they conjure up. On the flip side of this complicated English language, are the expressions that are not literal and do not make much sense if you have not heard them before. M has a fever and had to skip swimming today. When I told her she would have a make up lesson she was bursting with joy, imagining a class in which she would be smothered in lipstick and eye shadow. "Really? Make-up?" When I told her to her dismay that there was no maquillage involved, she could not understand why such a scintillating notion (make up!) was mixed up with an extra swimming lesson. When I told her we were not going out unless her fever went down she replied in smart ass tone "Down? Like downtown?"