Since Kōenji does not care about the inner workings of the class 1-D, he does not participate in any type of special exams but if there is a chance of expulsion he would participate so that he wouldn't be Expelled.
Class 1-D Edit
At first there is not much interaction between Kōenji and Ayanokōji. He calls him "Ayanokōji Boy." He also believes that Ayanokōji was the one to deafeat Kakeru Ryūen yet he has no proof of that.