The sea is the birthplace of legends.
Nia, a young mermyd of the Bluefin clan, has had one wish all her life -- to be an Avatar in her beloved home of Atlantis. The ten Avatars rule the beautiful and peaceful undersea city alongside the ancient Farworlders, whose magic keeps their world alive. To be an Avatar is an honor and a great responsibility, and Nia dreams of taking her place among the noble ten.
Now, at sixteen, Nia has a chance to see her dream come true. Atlantis is choosing its next Avatar, and Nia knows she is supremely qualified.
But there is something Nia doesn't know -- if she gets her heart's desire, it could mean the end of her treasured world of Atlantis forever. (from librarything.com)
The people of Oak Grove have stopped up the creek that used to run through their town, because they don't like to be anywhere near water. Eli and Trevor McGill, called Eel and Trout for their fish-like quickness, don't fit in at all with their strange fondness for meals of raw tuna and seawater. Their best friend, Martha Glimmer, feels out of place too, heartbroken after her mother's death. Dreaming of escape, the three run away, but a flash flood forces them home again, to think about what would make them truly free and face the truth - that Trout and Eel are the sons of a mermaid. (from librarything.com)