I'm pretty sure all schools would like you to show some sort of interest in their program. Showing up to interview because the weather is nice will get you a swift kick in the nuts.
Consider what you want in a program first. Don't pick a school because you've heard they like when you hang around campus. Then hit up some websites of schools to see if you like what you see. If something really sparks your interest, then look further. Some schools get all excited when you want to come visit (Pacific, Western), some can be a little less welcoming. Just be sincere and professional when you contact admissions for anything.
Keep in mind, face time, being annoying, sucking up, etc. won't do anything for you. It's very unlikely that it will increase your chance of acceptance or interview (don't read too much into rumors about UNLV and UoP in the last couple of weeks on the forum). But if and when you interview or fill out some secondaries, your answer to, "Why do you want to come to our school?" might be a little more believable if you've spoken to someone, visited, etc.
Depending on your time frame and location, look into sim clinics and open houses at schools near you.
If your school/club/pre-health department brings professional programs on campus for pre-health fairs/recruitment stuff, hit up the dent schools who come. If you can't get to their campuses, at least some one-on-one with admissions/student services people can be good. And you can snag a few pens and other school fodder while you're at it.
