It's my turn to do a speech to my classmates about a topic of my choice, but I have no ideas :) 

It can be on absolutely anything, the previous two topics were on 9/11 and on how to read bluffs in poker. Ideally it has to be interesting, and something that I can talk about for 15 minutes. Something related to the videogame industry is fine too, if you think of an interesting discussion point.

Thanks for the help xD

You could do a speech debating whether or not the entire "Everybody holds a 15 minute speech" idea is a waste of the students' time. When the speakers can choose any subject they want, it most likely won't be anything educational. Holding a speech for 15 minutes is good, and educational, but is it really worth each and every one of the students having to sit and listen to trivial things for 450 minutes (presuming there are 30 people in your class)?

That's probably something along the lines of what I would do, at least.

You might not be the kind of person who does that kind of thing, though. Whether you agree that it's a bit of a waste of time or not will tell you something, though. If you think that it's a waste of time, you should talk about something educational/the listeners will find very interesting to make it not be a waste of time for them. The problem with doing something video-game related is that over half the class most likely won't care, and it most likely won't be that interesting to the ones who do, as you have to do it at a simple level. You should try to make it something they care about, rather than just something you care about.

If you don't think it's a waste of time (and that presenting a 15 minute presentation is worth 450 minutes of listening), I can't really help that much. It doesn't narrow the field down at all, because it's just an excercise for you, and not for the listeners. Actually, if you think it's just an excercise for you, you should make it about something you'll struggle a bit to hold a presentation about. Like, a poem if you're a maths/economics/physics/etc kind of guy, or a physics presentation if you're an art person, as that's the way you will learn the most.

I kind of lost my point in all that. Here's the deal: You have to decide if you're holding the presentation for yourself, or for the audience.

If it's for the  audience, talk about something you think they'll all be interested in, and have learned from.

If it's for yourself, talk about something you're not an expert in, as that's the way you'll pressure yourself the most.

Hopefully that narrows it down a bit.

^^oooh good idea!

I really appreciate that advice :) Thanks

Awh, you're from Britain. I would have suggested "why teachers' unions should be outlawed" if you were from America. Not at all a position i agree with or advocate, but it would evoke a fun response

We have teachers' unions in Britain too :p

do a speech on why Neville is the true hero of the harry potter saga.

the prophecy, staying at school and organizing the resistance, going up against voldemort on his own without being forced to, slaying nagana (or whatever).... that should last you a couple of minutes and initiate discussion (I'm guessing most kids in your class are of the perfect age to be potter fans.

But you're forgetting Snape IS the real hero.

Well, my advice is... investigate something you're interested in, but you don't know much about. That way you learn things you're interested in, you have fun, and probably your speech is going to be more interesting.

the console wars, hardcore v casual gamers, 2012 election.

Do a speech on how the world is so messed up and propose possible solutions.