These are just samples; you may argue for one of these if you wish, but you aren't restricted to them. Another good place to look is in the list of reading response papers; they give a decent list of topics we've studied and suggestions about things you might want to argue about.
In this paper, I will argue that we have obligations of justice toward some animals, because we do have implicit agreements with them, even though they can't talk.
In this paper, I will argue that if death is annihilation, it is something terrible for the person who has died.
In this paper, I will argue that Aristotle is right when he says that post-mortem events can have an impact on your happiness.
In this paper, I will argue that Plato has not shown that justice is an intrinsic good.
In this paper, I will argue that Socrates in right when he thinks that the only thing that matters of happiness is the health of your soul, but that (contra Socrates) worse people are able to harm the soul of a better person.
In this paper, I will argue that Epicurus' proto-evolutionary story doesn't succeed in showing that we don't need Aristotelian final causes in order to explain the functioning of organisms.
In this paper, I will argue that Epicurus has not shown that death is annihilation.
In this paper, I will argue that Socrates' objections against Euthyphro's defintiion of piety as what all of god love does not successfully refute a Divine Command Theory of ethics.