Kathy, I think your point was proved by the responses you received to your simple "remember to be nice" post. WOW!!! I've seen those reminders off and on on various boards, but can't recall anything like the defensive, hostile "he did it first!" and "how dare you say anything!" posts on this thread. (Someone actually mentioned his "pee pee"? Really?)
Part of what I think you are saying, and some seem to not "get" is that this board does seem to have a certain core group who tease and joke amongst themselves, which is perfectly cool. However, this board is not their private one, and having some sense of courtesy to those who may not understand the inside joke and not appreciate "snarky" is
really not asking for too much.
And if little Johnny posts something you don't like, ignore it. It's been a LOOOONG time since I complained about someone "tattling.".