Refusing the tests is as simple as writing a letter to your principal and superintendent. You should also cc your refusal letter to your child's teachers. Your child's test will be scored as a "999" which is essentially a non-score. Again, your child will NOT receive a score. If your child is refusing the tests, instruct him or her to refrain from making any marks on the exam.
Below you can find a sample letter:
Dear School Administrator,
I am writing to inform you that my child, _______________, will be refusing the 2014 NYS ELA and Math Tests. My understanding is that this letter will be sufficient for my child to refuse and that he will not be required to verbally refuse these tests. I request that my child be allowed to read or engage in an alternate activity during the testing period. Please confirm receipt of this letter.