Real life Mother's call for help

I have a dilemma. My son had a 95% average and the teacher had a policy that all tests should be signed-unknown to me as she did not indicate it. My son did not get 6 tests signed --all the tests were over 90 and three were 100's which counted on a HW grade. This reduced his grade to an 85.

I spoke with teacher-to no avail and could use some tips in how to advocate for him. My son is in 9th grade.

As an FYI, NY state has state tests and my son got a 99% on his Math A regents just given in January. 

Why did he not get very high grades signed? He simply forgot, as we get home late and didn't know it would really count against him.

Please help.

Anna in New York

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