I like this girl but I dont see her often?

So I'm 17 and I like this one girl that I met through my friend. The first time I saw her she was with my friend and they both said hi to me and I really didn't notice her at all. Then for the next few days if she saw me she would always say hi and and honked at me twice when she saw me lol. A few days after that we were parked next to each other and she was in her car and saw me and said hi when I was walking to my car. I started to talk to her for the first time and she asked me if I wanted to go out to eat with her friends (there was like 5 girls in the car) and I wanted to say yes but I only had 6$ on my card lol. The next day she was having some car problems so I brought my friend who knows a lot about cars to come help. He couldn't figure out what was wrong with it but when we left she told me thank you and that I was so sweet and then gave me a hug. Don't think we just left her there lol, her dad was coming. So two weeks later when school is back from winter break, she doesn't park her car where she used too so the only time I see her now is every other day in the hallway during a passing period. She smiles at me and says hi but she's always with her friend so I don't want to start walking with her because it would be awkward with her friend just right there. And she told me she got her car fixed but that is the only communication we've had in a few weeks. I think she's interested so how do I find time to get to know her?