The magic treehouse takes Jack and Annie to Antarctica to search for the fourth secret of happiness for Merlin.

Taken to Antarctica by the man she thinks of as her uncle for what she believes to be a vacation, Symone--a troubled fourteen year old--discovers that he is dangerously obsessed with seeking Symme's Hole, an opening that supposedly leads into the center of a hollow Earth.

"Shy high school junior Riley Kowalski is spending her winter break on a research trip to Antarctica, sponsored by one of the world's biggest tech companies. She joins five student volunteers, a company-approved chaperone, and an impartial scientist to prove that environmental plastic pollution has reached all the way to Antarctica, but what they find is something much worse ... something that looks human. Riley has anxiety--ostracized by the kids...

"Sophie Scott is only nine years old, but she's going to Antarctica on an icebreaker with her dad, the ship's captain. During the voyage to Mawson Station and back, Sophie keeps a diary. She sees icebergs, penguins, seals and whales. She makes new friends, wonders at the southern lights and even becomes stranded in a blizzard!"--Back cover.

A boy and a mouse take a bumpy sea journey to the majestic expanses of the Antarctic, where they see the sights and meet new friends.

Meet Jack and his foster siblings, Ava and Matt, who are orphans. But they're not your typical kind of orphans -- they're geniuses. Well, Ava and Matt are, which sometimes makes life difficult for twelve-year-old Jack. Ava speaks multiple languages and builds robots for fun, and Matt is into astronomy and a whiz at math. As for Jack, it's hard to stand out when he's surrounded by geniuses all the time. When the kids try to spy on Dr. Hank Witherspoon,...