Please help me. How can I ignore them?

A few guys at Uni keep staring at me. I'm thinking about work and looking into the distance or looking at a lecturer, and these guys seem to think I'm looking at them. I even heard them talk about me, and they think I like one of the guys, when I don't. I just want to focus on my life, but I can't stop thinking about this. I am going back to Uni soon and I know they will be there, How can I ignore them? I'm no longer concentrating on my work because of this. Please help.