The Cay by Theodore Taylor

A boy and his mother flee the Carribean at the start of World War II, but their boat is hit by German submarines. Phillip ends up injured and afloat with an elderly black man - the start of their survival adventure.

This 1969 children's book was recommended to me by a former librarian who cited it as a forgotten favorite. I read online it has been criticized as racist - and while there are spots of racism, they're included to show how Phillip grows and learns. How the experience allows him to overcome perceived differences and learn what even his mother didn't know.

The book moves quickly - despite the fact it covers quite a bit of time, it's only 140 pages. To keep kids interested and engaged it's dramatic but doesn't dwell overlong on the machinations of life marooned on the island. I found it interesting and well told. 

Oliver and the Seawigs by Philip Reeve and Sarah McIntyre

Young Oliver Crisp's explorer parents have decided to settle down in one place. But within minutes of arriving at their new house on Deepwater Bay, his parents row off to investigate islands which are not on their map. And then, they don't return.

So begins a deep-water adventure for chapter-book readers featuring wandering islands, mermaids, a talking albatross, and sarcastic seaweed. Fearlessly, Oliver sets off to find (save?) his parents, and the boy who's seen everything discovers some really interesting new sights while he's at it.

I loved this highly illustrated juvenile fantasy. It's full of fun characters and a quick-moving plot that's just a little different than everything else.

Nation by Terry Pratchett

The big wave took everything Mau has ever known - his Nation (a tropical island) has been swept away, along with all its inhabitants. The young man lived only because he was on the water when it happened.

The same wave killed everyone aboard a large sailing ship - except one properly raised "princess" ill-equipped for primitive survival. Against the odds and a language barrier, together they survive, grieve, grow, learn to communicate, and build a new Nation with the refugees who appear one by one on the island.

As with any Pratchett book, there's a lesson, some philosophical questions to ponder, and a lot of just really funny gags. This one pokes fun of monarchy and manners, introduces us to the tree-climbing octopus, and introduces a new brand of Robinson Crusoe.