The #1 bestselling chapter book series of all time celebrates 25 years with new covers and a new, easy-to-use numbering system! Getting the facts behind the fiction has never looked better. Track the facts with Jack and Annie!!
 
When Jack and Annie got back from their adventure in Magic Tree House Merlin Mission #11: Dark Day in the Deep Sea, they had lots of questions. How big is a giant squid? What is a dragonfish?...

When millions of fish start dying off the coast of Hawaii and something is destroying hundreds of ships, the government enlists Max and the flock, a band of genetically modified children who can fly, to help get to the bottom of the disaster before it is too late.

"Ever since her father was lost at sea, Sophia has been moping around Aqualand, a marine theme park. But Sophia's world is turned upside-down when an "aquanaut" breaks into the park's research lab. To her amazement, Sophia discovers that the aquanaut is not what it seems: inside lives a band of goofy sea creatures! And when they all realize that Aqualand is more sinister than advertised, Sophia is determined to help the aquanaut crew free the park's...

The Truth about Dangerous Sea Creatures, full of eye-catching photography and interesting facts will thrill any young reader interested in the misunderstood creatures of the deep sea.

A hermit crab who has outgrown his old shell moves into a new one, which he decorates and enhances with the various sea creatures he meets in his travels. Poor Hermit Crab! He's outgrown his snug little shell and has to find a new home. And he does, with help from some friends who make the move less scary. Children facing change in their own lives will relate to Hermit Crab's story-and learn a lot about the fascinating world of marine life along the...

When his school of fish is attacked by a big tuna, Swimmy goes out on his own and discovers the wonders of the sea, so when he finds a new school, he helps them find a way to venture out and stand up to to the bigger fish.

Physically modified convicts are used in the Pacific for the exploitation of ocean-floor resources without diving equipment. But in the process they have become carriers of a microorganism that could wipe out humanity if they return to the surface.

Acclaimed naturalist Jim Arnosky will bring out your inner explorer as he explains why a puffer swells up like a balloon, how sharks locate prey in the darkness, and why some fish like to swim in the shadow of a manatee.

When Clark's mom makes brownies for school, Clark cannot stop himself from eating the delicious treat. --

"Dive into three new stories about Narwhal's favorite time of the year! It's the festive season in the world wide waters, and Narwhal is looking forward to cozying up with a good book, singing and partying with his pod pals and enjoying some warm waffle pudding. But most of all he's excited about the arrival of the Merry Mermicorn! According to Narwhal, she's part mermaid, part unicorn and completely mer-aculous! Jelly is of course skeptical about...