Jack and Annie travel in their magic tree house to the land of the mystical selkies to seek a magical sword for Merlin.

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

Evan and his younger sister, Jesse, react very differently to the news that they will be in the same class for fourth grade and as the end of summer approaches, they battle it out through lemonade stands, each trying to be the first to earn 100 dollars. Includes mathematical calculations and tips for running a successful lemonade stand.

When money disappears from fourth-grader Evan's pocket and everyone thinks that his annoying classmate Scott stole it, Evan's younger sister stages a trial involving the entire class, trying to prove what happened.

Jack and Annie travel back to nineteenth-century Ireland to inspire a young Augusta Gregory to share her love of Irish legends and folktales with the world.

The magic tree house carries Jack and Annie to New York City in 1938 on a mission to rescue the last unicorn.

The Aldens, while testing the latest version of their favorite computer game, are surprised to find messages directed specifically at them.

In this third adventure, Abby, her brother Jonah, and her friend Robin get sucked into the magic mirror and end up in the story of Sleeping Beauty, but when Robin pricks her finger and uses up the sleeping spell, Abby has to come up with a clever solution and a new happily-ever-after.

When an elderly friend is injured, the Alden children offer to help him with his window-washing business in their small town of Greenfield and agree to help him solve a riddle that has arrived in a mysterious invitation.

The Boxcar Children are going to summer camp and are looking forward to a week of new friends, exciting activities, and, most of all, the annual camp Olympics. As soon as camp begins, everything begins to go wrong for the Aldens-they lose their luggage, the camp flag disappears from Henry's cabin, and campers on the other team use one of Jessie's ideas to score points for themselves. Are some campers so desperate to win the Olympics that they are...