Without knowing a few more details about your research paper, it is tough for me to suggest a title that might be sufficiently narrow.
The first place that I would look to for inspiration is your thesis statement. If you thesis is sufficiently narrow, then you can base your title on that thesis statement. Your goal is to take the general point of your thesis and condense it into something much shorter. It also needs to grab your reader's attention.
I'm going to guess that your thesis is either about the cause of the dropouts or the effects of the dropouts. If it is the former, perhaps a title something like this: "Lack of Successful Student Learning Leads to Dropouts." I don't know if that is a cause or not, but it's a viable format. If it is the latter, try something like this: "The Dangers of Fresno's Increasing Dropout Rates." I believe that both of the titles are sufficiently narrow fpr your purposes.