CPS Interview

Does anyone have some helpful info for someone hoping to begin working as a child protective services caseworker?
During the interview process, they want me to review a fictitious case and gather facts from it, then later write up a summary of the facts and a conclusion including a decision on what the best course of action would be. Does anyone have experience doing this?
It's a fact-finding interview, which I don't think I've done before.
Are there any study materials you recommend (maybe something with cases in it for me to practice with)?