I've got a very active first-grader with severe autism that goes through periods of what seems like intense vocal stimming. He has these patterns of vocalizations that sound like ear-splitting, high-pitched shrieks. They definitely sound like a pattern, and you can identify exactly which shriek he is going to do next. He'll go through these phases where he doesn't do it at all for an hour, does it constantly for three or four hours, and then stops again. Also, sometimes it will dissapear altogether for 3-4 days, and then reappear with a vengeance. Sometimes he also randomly bursts out into REALLY LOUD bits of song lyrics. And he also does the Monday Night Football theme at top volume. Its not a communicative behavior - he does it when he's happy, when he's doing things he likes, when he's doing things he doesn't like, all times of the day, etc. I've taken data on it for 3 weeks and there is NO pattern. Right after he does it, he usually smiles, looks at the cieling and claps or flaps his hands. He's totally checked out -in his own world, excited about something none of us can see. We have a visual cue and replacement behavior program we're teaching during 1:1. Very occasionally he'll redirect visually to task when working 1:1, but he has yet to imitate the replacement behavior and the shreiking continues. In groups it is thus far hopeless to redirect. I give all the other kids headphones and we do the best we can. I feel like I need to step it up a notch, because he's the sweetest kid, and other kids are starting to feel the need to clobber him when he does it. Its like they've starting thinking, "hey, I've put up with this random shreiking for two years, miss bethechange - DO SOMETHING!" I've also tried gum, chewy candy, chewy tubes, etc. to keep his mouth busy with no luck. He'll chew, but it doesn't seem to affect the vocal business. Any ideas?