I note you are in Canada (from your profile)...any Canadian political issues you are passionate about?
Of course, some don't like politics, or discussing them. So, maybe about why studying <insert your favorite subject here> is really important, or why <insert historical figure here> should be remembered/was a really great person...or something like that.
Of course, if you do not want to do the "usual" topics...
-talk about an issue that not many people know about, but that is important to you
-read a philosophy book, choose a side, write.
If I were to choose...I would write about either 1) the future of biotechnology, covering the great advances we may encounter, how irrational thinking could hinder/destroy the process, and the moral issues that I think need to be addressed, but that shouldn't stop the science.
or: 2) the Federalist/Antifederalist papers or: 3) How I disagree with Socrates in some points & why or: 4) about US foreign policy and all the problems it has, all the solutions I think would work.