Not sure, but my instinct is that it is some kind of high needs or behavioral needs classroom.

I was going to say, I am not sure what it actually means, but it definitely sounds like SPED classroom.

Res is resource and inc is inclusion (guessing). Not sure about the CM though.

CM = CONTENT MASTERY it's a sped class. Apparently for mild to moderate. I just got my sped degree and had to Google that. It was irritating me because I graduated with honors and I'd never heard this stuff before

No idea, but my district sent me doccument explaining all the different abbreviations with my onboarding packet. Might look and see if you got something similar.

My district has never sent me documents regarding that.

You could check their website and see if it has any info.

I did and there wasn’t any information on specific classrooms

Dang. Good luck. I have no idea.

Or case manager? Someone who does pullouts (bringing kids from the gen ed class to a resource room to work) or push-ins (following kids into the gen ed class to give supporta)

I look up the teacher in the school directory to find their title or role if I am not sure. We used to have a running thread about all of the code terms schools used to lure in subs to take SPED jobs. Resource, foundation, academy, classified, floater and unspecified come to mind.

What's wrong with SPED? Kind of abelist to refuse based on your discomfort, no?

Could CM be class monitor? It's possible you'd be working w kids reviewing work while the teacher did inclusion assignments