Leo Borlock is the narrator of Jerry Spinelli's novel entitled Stargirl. Leo first becomes aware of Stargirl Caraway in chapter one of the novel. His friend Kevin hints at it, asking him "Did you see her?" in the opening line of the chapter. Then Leo hears her name for himself as it is called in his Earth Sciences class. Here is Leo's description of the first time he sees Stargirl:

"And then I saw her. At lunch. She wore an off-white dress so long it covered her shoes. It had ruffles around the neck and cuffs and looked like it could have been her great-grandmother's wedding gown. Her hair was the color of sand. It fell to her shoulders. Something was strapped across her back, but it wasn't a book bag. At first I thought it was a miniature guitar. I found out later it was a ukelele."

In Chapter 10, Kevin finally secures Stargirl's agreement to appear on the Hot Seat, a video program that Kevin and Leo create and produce. The first interaction between Leo and Stargirl is in chapter 12 when she is on the set of Hot Seat and uses her rat's paw to wave at him. She says the words "Hi, Leo," as if she is speaking for the rat.

In the prologue, Leo's mom puts information in the local newspaper about his interest in porcupine neckties, and the next day a tie shows up with no name attached. Later in the book, Leo finds out that it is Stargirl, but since Leo did not know it was Stargirl at the time, I don't count it as the first time he became aware of her.

In the prologue entitled "Porcupine Necktie," Leo tells about the time he read about himself in the family section of the local newspaper that highlights birthdays. In that article, his mother reported that Leo had a porcupine necktie collection as a hobby. Leo was fourteen years old at the time, which probably would have put him in ninth grade. A few days after the article about his hobbies ran in the newspaper, he found a birthday present on his doorstep and discovered that it was a porcupine necktie. It isn't until later in the book that he discovers it was Stargirl who had given him the necktie. He doesn't meet Stargirl until he is in eleventh grade, though, which is when the two of them are around sixteen or seventeen years old. Therefore, Stargirl first becomes aware of Leo Borlock when they are in ninth grade through the newspaper article, but the two of them don't officially meet until a couple of years later in eleventh grade.