On the issue of what to say/what not to say, I had a conversation several years ago with a "defensive" homeschooler at a basketball camp. I didn't know she was homeschooling her daughter and we were talking about how our kids were learning to get along with other kids. Our conversation went something like this.

Me: Oh, what grade is your daughter in?
HS mom: Well, she's 5 so she should be in kindergarten. But we homeschool and she is already reading on a first grade level.
Me: (biting my tongue furiously): Oh, that's lovely. So I was just thinking that as a five year old, it makes sense....(bringing the conversation back to the original topic).

It was really her tone that got me and the implication that her child was ahead because she was HSing--it was definitely a holier-than-thou tone. And I remain proud to this day that I didn't say what popped into my head, which was, "Wow, my son's in first grade a the local PS, but he's reading at the 7th grade level. Maybe you should consider PS since clearly they are doing a better job with my DS than you are with your DD."

From the perspective of distance, though, I do see her challenge in figuring out the right response to "what grade is your DD in?" I can see it would be something of a trick question if you have left the grade boxed life behind. I like to think she has refined her response a bit over the years.

So I don't have any advice on what to say, but I can say that this mother's response was most definitely a conversation killer!