The rear inside cover tells us that E. B. White's The Trumpet of the Swan 'was named an ALA Notable Children's Book'. The book has illustrations, a kind of Disney-style anthropomorphism certainly, but the vocabulary isn't particularly simplified, and I suspect many adults (young or otherwise) would really enjoy this tale of an outsider.
The story is about a swan named Louis (as in Armstrong) who is a swan who's mute, which is pretty serious when you're a trumpeter swan. (And there's some technical information about trumpeter swans, so this book is Educational, children, OK?) But Louis has a helper in the form of the human Sam Beaver, an eleven-year-old with a serious interest in wildlife. As you might imagine, Louis is a very smart swan, as smart — if not more — than humans, so eventually he decides that if he can communicate by learning English, it'll be a great advantage for him. We now have a fully literate swan flying back to his parents with a writing slate, but when he falls in love with the swan Serena, he still can't communicate with her.
So his father decides that to make a sound the only thing is to get Louis a trumpet, which he does by flying through the window of a music shop. But by the time Louis is learning to acquire an artificial voice, Serena has flown off. The other problem is Louis's guilt: he must raise money to pay for the stolen trumpet and the broken window. Eventually, having mastered the trumpet, he flies off to a summer camp where he saves a boy's life and is given a medal for it, then he flies to the Boston swan boats in the Public Garden where he makes a lot of money performing for the crowd. And so we have Louis, flying around with a trumpet, a medal, and a purse tied round his neck. Soon, he receives a highly lucrative offer to play a regular spot in a nightclub in Philadephia, and his bulging purse will soon make him a rich swan.
Yes, of course there's eventually a happy ending, and it actually reads much better than I can explain here, so I recommend it. On the back cover, John Updike is quoted as writing in The New York Times 'We are lucky to have this book.' I think so too.