Before we look into the ease with which you can get yourself some good paper titles to work with in as far as a debatable paper is concerned it is important to first of all understand what is required of this task. Since we do not yet have a particular topic in mind, let us consider what the blanket meaning of this paper is all about. A debatable title is one where you are required to present strong sentiments and arguments in favor of or against a particular subject. This is something that should not be so hard for you, having been in school for quite some time.
There is a lot of inspiration that you are supposed to draw from the normal debates that you conduct in class or through the debate clubs, and it is the same logic that you are supposed to implement when you are working on this particular paper too.
A good debate session will have an audience, and two sides arguing against or for the subject at hand. This is exactly what you should emulate when you are debating on your paper. Most of the time students make the mistake of choosing a side of the argument that they consider to be strong enough, or one that they can strongly argue for, or perhaps against and present this while overshadowing the other side of the argument. In as much as you might have found the easier way out, this is also the easiest way for you to get docked a lot of marks.
When you are selecting a topic for this kind of work, the most important things that you need to look at are the following:
You should never pick on a topic that you cannot support factually.
Before you select any title, make sure that you can cross reference the facts and use them to support your argument position.
Always remember that when you are writing this kind of a paper, you must present both sides of an argument, without appearing to favor either side. Argue strongly against and for the subject, and then when you are through with the argument, you can choose to make a closing statement where you will finally state your final position on the debate, but your paper must not show any signs of partial decision making.