Does this novel fulfill the expectations that Christopher builds at the start by labeling it a detective novel? First you may want to define a ‘detective novel’ perhaps using examples from other novels (a reference to Sherlock Holmes would obviously be very helpful).
Analyze the structure of the Curious Incident of the Dog in the Night-time and assess how it progresses, builds tension and keeps our interest. How significant is it that Christopher solves one mystery and finds another? How does the fact that it is all documented ‘in real time’ create a sense of immediacy?