The kids who do best at school are the fairly bright kids with lots of parental support (emotional and financial) who like to please.
I'd be a little careful with this popular truism. If you'd met my DD, you'd be the first to agree that "likes to please" is not, uh, the phrase that one tends to pin on her. We are also way below six figures for family income. DD is a straight-A student, though. Now, I would say that part of the reason for this is that she obviously has an excellent working memory and fast processing speed, and no other bottlenecks (no dysgraphia, dyslexia, etc), and is well-rounded with her abilities. (It's also fair to note that her grades *improved* when she moved to a gifted magnet.)