How should I approach this girl?

Alrighty, so I met this girl in my cl. I only began to notice her about a month ago, but she kinda caught my eye. She's really cute and seems like a nice person. Last week I finally got the courage to at least utter more than one word to her and I actually got to talk to her. I usually don't sit close to her so in cl I don't have the opportunity to turn to my side and talk to her, but I do get a chance after cl. I recently added her as a friend on face book recently and now my question is this; I really wanna get to know this girl, but I'm not sure whether I should try to chat with her on facebook or; now that I have physically spoken with her, just continue on speaking with her following our cl together. Which is "currently" the better approach?