These are YA, but the descriptions of them in the YA bookgroup's meetings made me decide to borrow them from the library.
The first, Stargirl, is from the viewpoint of Leo. When Stargirl (the name she picked and her folks thought was fine), who had been in homeschooling until then, first came to high school in an industrial city in Arizona, she wore frontier dresses and carried a bag with a sunflower on it, etc. She tweaks Leo's earlobe and bang! They become boyfriend/girlfriend. In the beginning, the other kids at the school liked her, but then they drew back. Leo tells Stargirl that if she was more normal, the other people would like her. She turns up in make-up, shorts and top, and fancy fingernails. The other people still don't like her. She and Leo are angry and she went to homecoming by herself, and surprisingly, people liked her.
The second, Love, Stargirl, is from Stargirl's POV. They've moved and her dad is no longer an engineer, but a milkman (!), and she's back to herself. She makes friends of a lot of people who need help and while she's doing that (in between homeschooling), she's writing Leo a letter from Jan 1 to Jan 2 the next year. The last page really seemed out of place to me. She suddenly tells Leo they will continue loving each other, but should each go with their own lives. If they meet together sometime, it will just be "a sweet collision of destinies."