The relevant post on Marginal Revolution.
Two quotes in particular. One is by Will Wilkinson:
Well, we’re atheists. I don’t intend to proselytize atheism to my kid, because I’m not interested in getting him to believe anything in particular. What I’m interested in is teaching him how to reason in a way that maximizes his chances of hitting on the truth. Now, one of the most interesting truths about the empirical world is that there are all these powerful systems of myth that are kept afloat by a sort of mass conspiracy, and humans seem disposed to pick one from the ambient culture and take it very seriously. But it can be hard to get your head around the way it all works unless you participate in it. Santa is a perfect and relatively harmless way to introduce your child the socio-psychology of a collective delusion about the supernatural. The disillusionment that comes from the exposure to the truth about Santa breeds a general skepticism about similarly ill-founded popular beliefs in physics-defying creatures.
and the other is by Tyler Cowen:
I say why not leave them guessing, hovering in a state of Bayesian Santa doubt? My parents never told me Santa “was real,” but they didn’t tell me he “wasn’t real” either, so I slid rather gracefully into my Santa non-belief. I don’t recall ever feeling disillusioned by a sense of loss and in fact those presents kept on coming. I even had a clearer sense of the appropriate channel for making gift requests, what’s not to like about that?
Related: The Santa deception Is Santa real On the care of young rationalists
All of the other takes on this topic start from a point, when a child (usually 5-9 years old) asks "Is Santa real?" Nobody yet asked "how to raise my child Santa-free?" What to say, when a two-year-old, who just noticed that there is this character on TV asks "will he come to me, too?" A toddler may not yet understand the concept of lie, of pretending, of things not physically existing. How to tell her, what will happen, what to expect, how and why other children behave differently?
My three-year-old daughter discovered Santa last spring, which finally forced me to think: how to deal with it? Ignoring the thing worked for three years, but what now? I live in an extremely catholic country (Poland), so I cannot be completely blunt about it.
In the end I decided to call it "the fairy-tale of [Santa] Claus." For me it has a lot of advantages: this is a story that can be told, retold, reinvented and everybody knows it. In addition, since the name includes the phrase "the fairy-tale", it has just as much validity as the tale of the Red Riding Hood or any TV character that she likes.
I tested some of her beliefs about "Miko". I opened the box with books intended for gifts in front of her. When she wanted to read some of them, I explained that she cannot yet read her book, because she'll get it on Christmas Eve. She asked "is it from Miko?" and I replied that in some way it is, but I bought it. She didn't insist on reading it right now. A few days ago she helped me wrap some of the gifts. She commented that action "Miko brought these so we can wrap them and give them as gifts from Miko."
Malcolm told me, that he likes best the strategy, when you say that Santa Claus is a game that everyone plays. People pretend that there's a big guy in a suit who does the thing, and if you ever let down the pretense to your friends, you lose the game. I'm not entirely convinced by this strategy - it may be too complicated for a 2- or 3-year old (since my daughter didn't wrap her mind around the information that I bought the books).
What are other strategies that you use? Or which ones you don't like? Why?