@boomerang,
My experiences with school administrators, as respect myself and my children, has not been wonderful, but maybe, in this case, they have given it sufficent thought. I certainly wouldn't be surprised if they didn't, but if your neice hasn't demanded that they answer these questions she should, and if they don't have an answer, she should go up the chain of command demanding them.
If this was a case of a school just wanting to dump a student with whom they are having problems, it's not one where the student should be anyway. If your neice doesn't move her daughter to the charter school they recommend, she should consider somewhere else.
I would suggest that she visit the charter school though and talk to administrators and teachers, rather than assuming it's not the right place for her daughter because of some internet reasearch alone.
By the way this sort of thing happens in school throughout the country. Maybe not in terms of recommending transfer to a charter school, but in not be willing to address the specific needs of a problem student. It's not just Texas.
