D.P.
It's everywhere but yours sounds like an extreme case. Frankly, I'm surprised the teachers and principal are so involved.
All I can suggest is that you (and any other *normal* moms) immediately become Switzerland and refuse to get involved in the gossip and snarkiess of the situations.
Ignore the Stepford Moms when they boss you around and you guys follow the teachers instructions.
I often wonder if moms like that would benefit from purchasing a *real* life!