How do I tell a girl I don't want to hang out or be friends?

So I barely know this girl. She went to my school when we were in 7th and 8th grade and now that we've graduated, she suddenly wants to be friends and has asked me many times if I wanted to hang out with her. And I mean, I barely know her. And I'm afraid it will be ackward because we are so different and I'm not like her at all. So I was wondering how to nicely say I don't want to be friends with her and I don't want hang out.How do I tell a girl I don't want to hang out or be friends?
Just be honest!!! Honesty is the best policy as I would say ;) xHow do I tell a girl I don't want to hang out or be friends?
Well, I'm just saying different friends are the best kinds sometimes. If she wants to be friends with you, maybe you should give it a chance!