Dude, you dont have to think about shit like this.
just put together a nice presentation...very nice research done btw...and tell the whole class and your professor about cannabis.

Even more, they might understand it and become marijuana advocates themselves.

but the worst that can happen is they put you down for being a pot-head and who the FUCk cares what they think anyway...thats just my:twocents:

Good luck with your presentation hope it goes well