I feel that you're a mom that only wants the best for her child. You didn't say anything bad about the teacher or the school, and you never said that your daughter is miserable as a result of not being invited to these parties. So it sounds like your daughter is ok and the school is ok but the other moms don't want to talk to you for whatever reason. Whether you keep your daughter in her current school or send her somewhere else, you could find these 'mom cliques' anywhere. Something that has helped me get 'in' with other parents is getting involved in school activities, such as chaperoning class trips or volunteering to help my kids teachers. I could care less about being a member of a clique, but I have found that my kids have been invited to more playdates and parties as a result.