Ponyboy Curtis is certainly the best student of all the characters mentioned in The Outsiders. In the first chapter, Pony tells the reader that "I make good grades and have a high IQ and everything." Darry scolds Pony that "you must think at school, with all those good grades you bring home, and you've always got your nose in a book." Pony apparently makes mostly A's and B's, since Darry expects him to "make sure they stayed A's."
But after the deaths of Bob, Johnny and Dallas, Pony's grades slide, and he was "lucky if I got home from school with the right notebook." He left his shoes in the locker room at school and was "lousing up my schoolwork, too."
I didn't do too badly in math, because Darry checked over my homework... but in English I really washed out... Now I was lucky to get a D on a composition.
His English teacher, Mr. Syme, took pity on Pony, and promised to give him a C for the final semester "if you come up with a C grade" on a composition theme. Eventually, Pony decided to tell "their side"--Johnny's and Dallas'--and the composition Pony wrote began, "When I stepped out into the bright sunlight from the darkness of the movie house, I had only two things on my mind: Paul Newman and a ride home..."