It's the first in a series of books by Dave Barry and Ridley Pearson that build an unauthorized prequel to J.M. Barrie's Peter Pan and Wendy, the 1911 source for Disney's 1952 Peter Pan character.
Here's the lede:
Orphaned kids, Pirate ships with huge brassieres for sails, near escapes, giant flying crocodiles, shipwrecks, mermaids with sharp teeth, massive storms, belch humor, talking porpoises, and bashing the bad guys with coconuts.
What more could you ask?
And don't forget --
"Pirates. It's a good thing they're idjits."