Bridge to Terabithia
How we cite our quotes:
The stream was a little lower than it had been when he had seen it last. Above from the crab apple tree the frayed end of the rope swung gently. I am now the fastest runner in the fifth grade. (12.21)
Numbly, Jess reflects on his achieved and once-longed-for ambition. It's morbid, but he's at the very place where Leslie died, looking at the rope that failed her when she was crossing the creek. Implicitly, we understand that Jess feels like he might have failed her too, by not being there to convince her to wait and go to Terabithia only when the creek calmed down. Instead of thinking about those things, he turns his attention to the fact that he's become the "fastest runner."
He was suddenly ashamed that he'd thought he might be regarded with respect by the other kids. Trying to profit for himself from Leslie's death. I wanted to be the best – the fastest runner in the school – and now I am. (13.45)
This isn't how Jess wanted to win that race or become "the fastest runner" at all. Now he has what he wanted at the very beginning of the book, but it's meaningless. He's the fastest runner now, but it's not because he improved, or trained harder, or got fancy new running shoes. It's because his competition can't race against him anymore.
Now it was time for him to move out. She wasn't there, so he must go for both of them. It was up to him to pay back to the world in beauty and caring what Leslie had loaned him in vision and strength. (13.60)
By absorbing Leslie's ambition into his own, Jess's desire for shaping his future life becomes deeper and more profound. It's no longer about being just the fastest runner in fifth grade, or creating awesome drawings. It's about making a lasting contribution to the world that reflects what Leslie taught him and helps memorialize her in another way. Instead of striving for records or material things, he will "pay back to the world in beauty and caring what Leslie had loaned him in vision and strength." Because she can't keep on giving that "vision and strength," he'll take on the responsibility of turning those qualities into "beauty and caring," and send them back out into the world.