I agree with teaching secular ethics and critical thinking. I prefer people to arrive at conclusions by themselves, rather than being told flatly what's "right" or "wrong".
For example, if a child believes that the tooth fairy exchanges their teeth for coins, or that their parents do it, it's of no value to her to say "it's your parents" (or indeed "it's the tooth fairy"), but rather you teach them to question their own beliefs. It doesn't really matter which conclusion they come to, so long as it's done by their own effort, as opposed to what they've been told.
However, things like this can be addressed in a debate where someone can defend or represent an opposing view. Just in the context of teaching, i'm talking about.
In regards to evolution, i should say, that proven scientific fact should obviously be taught in the science classroom. You don't skip over the truth because it might offend someone.