When my son was young, I learned early not to ask a question you are not prepared to accept the answer to. In other words, phrase it so that (as much as possible) their answer are acceptable to you. For example, do you want hot dogs or pizza for lunch? This way, they can't say spaghetti when they are wearing their good clothes. Or at least, you can say, spaghetti is not on the list. But they will still find a way to get around it and crack you up sometimes.