I would have to say that Scout and Jem (from the novel To Kill a Mockingbird) do not grow from children to adults over the course of the novel. Given that both are very young over the course of the novel, going from 6 to 8 and 10 to 12, the children are still children at the close of the novel.
While one could easily argue that the children do mature, they are far from adults. The actions of the children throughout the novel are those typical of children (they dare each other to touch the Radley home, have extended conversations about gum, and sneak out of the house). These are by no means adult behaviors.
In the end, the children do face an act only adults should have to face (one of being attacked--not saying that anyone should have to face this, but least of all children).
Overall, the children do learn a lot about life, the society they live in, and the hatred of the people around them. These are typical things that children learn about as they grow up.
By no means can either Jem or Scout be considered adults at the close of the novel.
I would say that Scout thinks so. At the end of the novel, she comments that there was nothing left for her and Jem to learn except, perhaps, algebra. These children have, in the course of two short years experienced a liftime of life lessons ranging from tolerance to courage. Jem learns about forgiveness from his interlude with Ms. Dubose, whereas Scout learns about it from Uncle Jack, and to a lesser degree from Aunt Alexandra. They've deal with racism on an institutional level, they learned about isolation and and perspective from their saviour and friend, Mr. Arthur Radley. Scout and Jem had a head start on maturity from the get-go with Atticus as a parent. His wisdom, quiet authority, and supreme integrity teach them everything they need to know to be successful both as children, and more importantly as adults.