marie cc:i was forced to send my children with my mom so in the end cps was called and i am now being investigated with the chance of them being taken.
Unless the children are in any danger, I highly doubt they would be removed from your mother's care.
I suggest you cooperate with CPS as much as possible. I would also forget the "defamation of character" thing.
The school principal may have over reacted by calling CPS; However, there might be more to this than you have posted here.
I'm not a lawyer. This is only my opinion /suggestion. Most Replys' are based on information provided by the "original post" (OP).