A disagreement between Coral, Filly, and Manta, three young mermaids who work together to build and safeguard the reef that is their home, must quickly be set right.

"Ayla lives on a beautiful tropical island surrounded by a coral reef. Her mom is a marine biologist, and every day, the two go exploring together. One day, Ayla notices that many of the fish have disappeared, and the once-vibrant corals have turned pale. She and her mom set out to save the corals--but is it too late?"--

"The fairies are going green! The fairy king and queen have just put together a new team of seven fairies for a very special mission. They are the Earth Fairies! Together, they're going to work their magic to clean up the environment. But they can't do it alone. Luckily, Rachel and Kirsty are ready to help! Coral the Reef Fairy's magic keeps the reef environment healthy. But Jack Frost's goblins have her wand and underwater environments everywhere...

A young boy's dream sends him on an underwater journey through a coral reef. Includes factual information on coral reefs and the animals that live in them.

A sea horse leads the reader past coral reefs and underwater creatures to a sea horse family hidden in a cave. Includes notes on coral reefs and various marine animals.

The inhabitants of a coral reef are threatened when a shady real estate deal started by the greedy Groper floods their area with poisonous waste.

The sea creatures of Higgin's Hole, led by Petronius the seahorse and Lutus the lobster, defend their ocean home from a pack of three great white sharks, led by the infamous Tacitus.

In the first story, the Alden children uncover a plot to sabotage the Greenfield Bears baseball team. While visiting the Florida Keys, the Aldens encounter suspicious characters, strange incidents at night, and a plot to steal valuable coral in the second story. Finally, in the third story, the Boxcar Children go to summer camp, where they suspect that someone is cheating during the Camp Olympics.

On a trip to a coral reef in the tropics, the Critter Kids become shipwrecked on mysterious Octopus Island and run afoul of Dr. Yes and a giant octopus.