How fo I get her to notice me?

I'm 14 and I think I have fallen in love. I laugh with her, I joke with her, I talk to her but she seems to always put me last in everything my class do as a group. I have felt this intense burning feeling in my chest and whenever I stand next to her or look into her eyes I just want to kiss her. I've felt like this since the moment I saw her 3 years ago. We used to go to each others house every da about a year ago, then I asked her out and she said no. I thought, yeah, let's get over her, but I think I want to persevere. I even wrote her a song (which I haven't played yet). But she doesn't voluntarily do anything with me. She seems to put me second to other guys. How do I get her to do those things with me? I think she's the perfect girl in the world, we share the same values, we have the same sense of humor (i always seem to overthink the funny things I say to her in case I say something unfunny in the process). I want to spend my life with her. This is a cry for help. Girls, would you date a reasonably good looking guy that cared for you and loved you for what you are-and wrote you songs?