I agree with the other reviewers on the main points. Hilary McKay is quite funny although I think her humor is most likely to be appreciated by adults. One of the pleasures of these novels is the way the Conroy girls resist the adult world and the way that adult world reacts in response.(The mother is described as being furiously bewildered toward the end of the book. A state that I bet most parents are familiar with.)The other reviewers mention that the girls' troubles start when Ruth signs up to sponsor the education of an African boy even though she is too young to do so. She and her sisters have to raise ten pounds a month.The thing about these girls is that they seem so clueless in the world. Maybe because they are such great readers they seem to have no ability to judge how their schemes will work out in the world let alone how moral their schemes are. The results are comical, annoying, somewhat dangerous and culminate in what would have been petty theft if it had succeeded.The amazing thing is that McKay has succeeded in making them so likable. The girls have an obduracy about them that seems so like so many of the kids I know (including my own daughters). This is what I mean by the darkness of these books. McKay has presented us with characters as morally self-serving, as amoral as many kids really are. She has also presented us with a good story about such kids growing up a little(not least by having to face up to their mother).I have been reading these books to my girls (5 and 7). They may be a little young for the books but they have lots and lots of questions about the girls and my daughters like these books very much. So do I. I recommend them wholeheartedly to parents who want to read something to their kids that will amuse and bewilder them as they read and will lead to good discussions.