When her class at Trident Academy visits a pod of whales, Kiki Coral must overcome her fears with the help of her friends.

"Not one of the merkids in Shelly Siren's third-grade class can believe the shell-shattering news: Shelly is a princess! A real princess! It's been a well-kept secret in Trident City, but now the word is out, and Shelly doesn't know how to act! Should she start wearing a glittery crown? Or move to a grand undersea palace? Will her friends have to call her Your Highness? Being a princess may be exciting, but Shelly's not sure she can truly play this...

Shelly, Echo, Kiki, and Pearl are spending their school vacation at Neptune's castle! Shelly's aunt, Queen Edwina, has invited the girls to stay for a whole week, and while they're there the girls can't wait to visit the Royal Orca Museum, see the Palace Library, ride seahorses, and maybe even attend a royal ball. Shelly is nervous about meeting her royal family, especially since she's never felt like a princess. But when she arrives at the castle,...

Shelly Siren loves playing on Trident Academy's Shell Wars team. But is she ready to complete in the Shell Wars Championships in the fintastically famous city of Atlantis? As part of their trip, the mergirls get a tour of Atlantis and swim through Poseidon's Temple where Shelly sees a spookfish, which according to legend, carries a horrible curse.

Echo's third grade class visit the Titanic and figure out a way of including their new classmate, Anita, who is confined to a wheeled chair.

There are some pretty weird grown-ups living in Bailey City, but could the new gymnastics teacher really be a witch reciting rhyming spells? The Bailey School kids are going to find out!

Of all the creatures in the ocean, sea horses are Echo Reef's favorite. They're sweet and gentle and they glide through the water so gracefully. When Echo discovers that Rocky Ridge, one of her Trident Academy classmates, has his own pet sea horse, she wants one right away. Not everyone agrees sea horses should be pets, however. Perhaps they are happiest when swimming freely. But Echo thinks that if Rocky can make a sea horse happy, she can too! Can't...

Some of the kids at school wonder if Mr. Jolly could be Santa Claus. He keeps the building cold as the North Pole and the school building magically clean. Can he make a miracle happen?

There are some pretty weird grown-ups living in Bailey Cit. But could the new school nurse really be a Martian trying to spy on the students at Bailey School? The Bailey School Kids are going to find out!

With humor, suspense and mystery, this popular series continues as The Bailey School Kids investigate a new soccer coach whose spacey stare has them worried. Will her hard-driving practice sessions turn them into winners or zombies?