Well, we tried something that worked, so I thought I would share.
We'd gotten an email from DS's teacher. He's had only one meltdown since she's know him, and even though she's a great teacher and works with him really well, and is very accommodating - I don't think she really believes that DS is disabled (which he is less and less so, but there are still things he really struggles with.)
Apparently today he came back to the classroom from a music lesson to find other kids sitting at his desk. He reacted by taking a dry-erase marker and writing something like "KEEP OFF" all over it...and unfortunately, the marker stained his desk. She then asked him to write about being angry, and he wrote (and blacked out) some curse words. She sent me an email because he'd told her he had no control over himself and couldn't help using those words, and she was worried about that.
At any rate, we resolved to talk about it with DS, who spent the entire evening melting down, throwing things, yelling in anticipation. In a moment of inspiration, I created a blank document on my laptop, landscape style, and set the font to 48 point bold type.
I typed:
Dad and I know you had a bad day. and turned the laptop so he could see it
(nod)
We are trying really hard to help you.
(nod)
I understand. However, you can’t take your bad day out on us. It’s not right. OK?
(nod)
Just because we don’t know what to do doesn’t mean we aren’t trying our best.
(nod)
OK. That means you need to try your best, too.
We went on this way for almost an hour, saying nothing, he finally started speaking responses, and we'd type in a response (the large typeface meant we had to limit our words to just a few) and finally determined that he was really ashamed for having done, essentially, nothing wrong. We were able to reassure him and make it better and nobody lost their temper in the process!