Is he interested in me (Easy 10 PTS.)?

[2angel7]

There is this guy that sits next to me in my French class. Today we were supposed to work in groups. We worked together and we helped each other. We made a bit of small talk. He asked me for my Facebook page. I told him that I don't have one and I would give him my number. He didn't even give me time to write it down. He wrote his number in a piece of paper. Our class time was over and he said bye and he left first. I texted him saying hello and he answered back with hello. Why did he ask for my Facebook? Is it weird if a girl doesn't have a Facebook? Is it easier for guys to talk to a girl on Facebook or by phone (text)?