You can put flyers virtually anywhere at a university. I've seen them on light posts, trash cans (thought that's not ideal unless it's a big, easily-readable flyer; who wants to stoop down?), walls, etc.
The thing is, everyone else is using flyers too. Make yours stand out. Make sure it has color - the premium is worth it, but if you're really concerned, then find a local print shop and bring your own paper; you can really drive the price down like that.
Also, if it's bigger than the rest, of course it'll get noticed as well. Maybe even just a 11"x7" or a legal size. 11"x7" isn't bigger than the standard 8.5"x11", so while it doesn't provide as much printable area, the longer shape helps attract attention since it's not as common. Same with legal size.
Also, if you can afford to hire someone to pass flyers or notices out, it will be worthwhile. Usually, college students don't say "no" to someone handing them something; they take it and move on. It's best to be direct, so rather than asking, "Hey, do you want to learn about [...]?" say, "Here, take this flyer to learn more about [...]." I often see many students around campus with the same flyers as me when people passed them out in this manner. One I remember was for Paranormal Activity 2.
A sneaky but effective way to hand things out is to make the person think you need help. I only say that because someone else used this same tactic on me the other day. I admit, I should have known he was going to try to advertise, but he looked confused and asked if I was a student there, so I initially thought he needed help with something, and I didn't have the will to tell him I wasn't interested when he started his pitch.
In that above case, the man wasn't actually selling anything. He apparently a "monk" handing out the book called Bhagavad Gita. Sure, he asked for a donation, but the book was free. I saw another student talking to another monk just minutes later, and between one class I saw two people with the same book, so I'm assuming this technique is effective.