Reinforcement:

How are you adjusting reinforcement to reduce maladaptive behavior? Can you reinforce a more appropriate, alternative behavior to replace the maladaptive behavior?

Previous histories of maladaptive behavior in peer interaction or in interaction with authority both suggest the importance of addressing this topic in a systematic fashion. If staff can decipher the function of previous and inappropriate interactions (i.e. why the student is engaging in that inappropriate behavior), then the goal becomes to replace that behavior with something more appropriate. Why I do something is not necessarily wrong but how I say it or act on it may be very wrong. Give the student a way of conveying his message better, whether with authorities or peers.

What are some reinforcing consequences you can deliver either immediately following the desired behavior or following a practice session– things that this particular student enjoys, wants, seeks out, etc.?

Practice with role-play scenarios may agitate a student who has difficulty curbing reactive statements and behaviors (rolling eyes, exclamations, signs of frustration, etc.). Building a new pattern of behaving in response to authority, to direction, to a suggestion to try another way, or to an urge to say something without attending to the audience can be taxing. Build one skill at a time to a level of fluency. Initially short intervals of practice may be followed by alone time activities or highly reinforcing and comforting activities.

Are you using labeling and social praise to make the contingency between desired behavior and reinforcing consequence clear to the student?
What reinforcing consequences can you arrange that are more naturally or intrinsically connected to this targeted behavior? 

Your efforts to coordinate with other authority figures in multiple environments will be helpful. Others may not recognize that simply labeling what the student does well and praising him for it can serve to strengthen the new behavior.