The date in the predicates is fixed when you create them, i.e. , your getStartDateForDay: and getEndDateForDay: will not get called again automatically. You need to update the predicates when you detect that the day has changed.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.