take into head

take (something) into (one's) head

To believe that something is true. Take it into your head: I'm in charge until Mom gets home, so you have to listen to me. A: "Why is Johnny holding his breath?" B: "Well, he's taken it into his head that holding his breath will make him taller."
See also: head, take

take something into one's head

Fig. to get an obsession or overpowering idea into one's thinking. George took this strange idea into his head about fixing the car himself. I don't know why she took that strange idea into her head.
See also: head, take