One suggestion was to create Rules of the House....and put them in writing. While I was initially resistant to the idea, as I thought about it more, it seemed like we didn't have much to lose. And, being a writer, it's not much of a stretch for me to put pen to paper.
So....I found a really cute pig notebook and gave it to Seth, and he and I together created pages of "rules" for acceptable behavior. And, surprisingly, it seems to have had a strong, positive impact almost immediately. He is very conscious now that we have particular expectations of him and that there will be definitive consequences.
He actually now comes home from school spouting new rules he wants to include. It's kinda fun and gratifying to have a truly constructive mommy 'n me project, and we're grateful to see him responding so that life at home can be a bit easier....if not perfect....for all of us.