What do I do with a neglectful rude school?

My son has ADHD. He has been going to school for 4 to 5 months now and I explain to his teacher in the beginning that he he has ADHD. She told me to fill it out on the paper and she told me that she would be in contact with me. She never got in contact with me and my sons grades continue to slip! I went to Barnes & Noble to purchase some practice math. Also at the parent teacher conference I asked his primary teacher who just returned she was out for 4-5 months I asked her if they send the kids home with math homework He has never bought any math homework home since the beginning of the semester he brings home other homework she claimed they have math homework that get sent home and she does not know where all his homework went she also was not aware that he had ADHD I spoke with the principal about this matter The principles rude. And said I should've spoke with her earlier about the situation but how am I suppose to know all this I spoke with the teacher! She also said that there is a 504 plan that my son should have been on and I just now heard about it 4-5 months into his school with a grade of 69 in math his other grades are fine! She said the teachers don't keep info about a child ADHD The principals and the counselor's had attitudes towards me another occasions now that i have to work with them to get my sons math on tract kind of frustrates me because I don't know if they will be trying The principal was hard to get in contact with I can't afford private school

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