okay there is one girl in college that I really like, so I just walked up to her and I started socializing with her, but I found out that she's a sophomore and the problem is that I am still a freshman, but we are the same age!
now the question is what should I do? Should I tell her the truth and see how she reacts or just lie? And wouldn't be so random if I ask her for her number on the second day?

Get to know her first don't jump straight in at the deep end let her see the real you and get to know you don't be telling lies because then if you do get together then it'll be based on lies and that wouldn't be good

If you tell lies you will get caught. Coming from someone in college, once you are here, its not about the number of credit hours but how mature you are and having confidence in yourself. College girls can tell if you are confident, and that's gets them interested. I have known many young ladies who have dated guys who were younger. You two are the same age, there should not be a problem. Ask her out if you like her so much, what's the worst she can say, "No!" But if she does say yes, take her on a date where both of you can be comfortable and yourselves. Not the movies. Maybe dinner, but have something else planned... putt-putt, the circus, or go to the mall (know that's a fun one, that is when she will flirt with you and girls like to take guys shopping)

Leave the lies for the players, and be yourself and get to know something about her. Take your chances.

Not all girls like shopping you know

I hate shopping,I do mine on a Friday and on the Wednesday I'm dreading it

So not all girls like shopping

And if you really like her don't rush in to it when you nothing about each other

there nothing wrong with dating an higher class girl... normal.. if she doesn't like for who you or or just simple that you are a under classman then she not worth it ^^

uhm.. first you have to get to no her more... then later on the week... ask number... within weeks you have to ask her out.. or you will step into the "friend zone"

if I am wrong please correct me

You're in college. It doesn't matter how old or what year you're are in. Just talk to her and start to become her friend. I'd say just keep talking to her as you see her. Say hi and what's up, and if she always reacts positive then ask her to hang out someday. If she kind of shys away, and isn't enthused when you talk juts try to not take it as an insult towards yourself. There's dozens of girls at college so just one that you aren't close with at all yet turning you down should get you down. Become her friend and if she seems into you, then you can slowly step it up.