There are several kinds of fiction in children's literature:
Historical Fiction - Set in the past, these are stories that could have happened. Each story reconstructs events of past times.
Mystery - Stories where crimes or puzzles are solved by some of the leading characters. In most of the children's books, the crimes can be non-violent.
Realistic Fiction – Present stories in a context of “what if” so that the events could happen in a real world scenario. The characters seem real and the setting is usually contemporary.
Science Fiction – Stories are primarily based on extending physical laws and scientific principles. Frequently set in the future.