Help, school zone speeding

This morning I passed a school zone then was stopped by a black policeman. He said I drove 35 at a 20 limit school zone. first of all i didn't know how fast I drove because it is rush hour. Also some cars before me passed without any problem. I want to complain. Do you think what is the best strategy for me to handle this problem. Thanks a lot. By the way, i have to go the judge he marked on the ticket? May I go others? Thanks