Got it. If you hold your finger on the home page until the Widgets etc. choices appear at the bottom of the screen, one of the choices there is Settings. If you choose THAT Settings menu, the first screen that pops up has the Feed toggle at the top. If it doesn't, and a list of options appears instead, choose Your Feed, and that should bring up the screen with the Feed toggle at the top. Toggling that off brings up the question screen (Do you want to ...) and choosing Yes kills the Google Now window and all of its cards. Bingo!