I'm going to present a argumentative speech in front of my class. The topic must be interesting enough. I have to get all the attention of my audience, friends, even my lecturer. I have no ideas on it, so please tell me what to do?
Since this is a school project you don't need to be on the side that you decide to take. You just need to educate yourself enough about the side you take. And make sure you stay away from logical fallacies.
examples:
Abortion
Right to die
Drug Legalization
The war in Iraq
gun control
there are many more topics out there, and I am sure sure someone will already pick each of the above, so do a little digging, really the first person who matters to impress in the audience is the lecturer, then yourself, then your classmates, your friends not so much.
I did a similar talk in Collage about my opposition to advertising to minors (this was while I majored in Advertising) so sometimes hitting close to home in opposition to an ethical question in your chosen major could be a very ideal learning situation for yourself.