Having spent some time searching on the topic seem to have helped a number of people in asking better questions. As everyone's still formulating their focus, you should actively question your questions as you run across new information that matters. In several cases, it seems like the students sub questions could work better as the main research question. Just keep looking for information, that's the only way to get things to "click" and help you formulate the right questions.
I've asked a number of people to re work their research questions, reasons,
a) Too vague, the question is more of a topic/issue in its current state. - My rec. is to look for more information till something clicks. I don't think I saw a case thats too narrow yet. Lack of confidence on the topic is often associated with lack of information on it, the answer is to keep looking.
b) Topic/issue/question that already has fairly clear set answers, mainly the ones surrounding processes, "how to do/make x y z," descriptive ones, "what is issue x", or the what are pro/con ones. Those are good topics for a short topical paper, but would not fit well with the purpose and activity of the course as we move forward. That said, almost any topic can be researchable, the key is in the questions, and you should see me if you're having trouble with it.