Everything you need to understand or teach Fish Girl by David Wiesner.
Donna Jo Napoli’s young-adult graphic novel details the life of a mermaid known as Fish Girl, who lives in captivity at an aquarium called Ocean Wonders. A man who calls himself Neptune runs the aquarium and claims to take care of Fish Girl. However, Fish Girl begins to realize that Neptune is not who he says he is, and with the help of her octopus guardian and her human friend, Livia, Fish Girl decides that a life of captivity is not what she wants. Fish Girl decides to explore the world outside of her aquarium. The book is illustrated by David Wiesner, and Napoli explores themes of identity, friendship, mystery, captivity, and loyalty.