I took dd out of pre k recently for the same reason. We had issues relating to gt anyway but the bullying was the final straw. All I wanted was the teacher to acknowledge a problem and shadow / work with the agressive kid. Instead she victim blamed my dd. in the end I cut short our meeting told dd to get her bag and walk out never to return.

I know our kids need to learn to stand up for them selves and that we can't fight all their battles etc, but at such a young age I wanted my dd to get the message loud and clear - she will never be subjected to violence if hostility without having someone to defend her.