Adventures in Public Transportation

I was taking the bus in Taipei city last night, just minding my own business. I had earphones in, and finally got a seat about halfway through the trip. There was a teenage girl sitting next to me, and after about 10 minutes she tapped me on the shoulder and showed me her cell phone. On it, there was a message that said something like:

"Hi, what is your name? Can I make a friend with you?"

I was a little confused at first, so I just looked her. I wasn't sure if this was a message she received and didn't know what it meant, or why she was showing it to me. Finally I asked if she had typed it. She nodded. I tried to chat with her a bit but she didn't really speak English, so I spoke with her in Chinese. I invited her to bible study, gave her a card, and fortunately, it was almost our stop. After I got off, she followed me a little ways, and I said "bye-bye" in a very friendly voice, phone in hand as I was meeting someone and needed to call them. Then she asked "Do you have a cell phone number?" I hesitated, not really wanting to give my phone number out to a stranger, but also not able to lie since I was holding my cell phone in my hand at that very moment. I thought it would be too mean to give her a fake number, so I finally gave her my number and said goodbye.

About 15 minutes later I got a text message:

"Nice to meet you. Is it ok if I call you to practice my English?"

I replied that i am very busy, but would be happy to talk to her if she came to the class next Friday.

What would you do?