I want to make my Buy A Friend A Book Week recommendations YA books that aged ones can also enjoy. My first two choices, sadly, are out of print. That's okay, though, because this book may even be better.
Before there was Georgia Nicholson, before there was Bridget Jones, there was Adrian Mole by Sue Townsend. And his adventures, taken together as The Adrian Mole Diaries are available for young and old alike to enjoy.
Adrian is supposed to have been huge in England back in his day, and Helen Fielding has admitted to being influenced. So you could call him the boy who launched the chicklit journal craze. He is, however, significantly deeper than his female followers, though still very funny. I have been a fan since discovering him in a local middle school library.
Quite honestly, I don't know if this book was originally published as YA or if it is being promoted as YA now. It deserves to be better known in this country and could easily be a cross-over book. So go out and buy it for a teenager or adult you know.