The mysterious disappearance of a reclusive neighbor's cat involves the Boxcar children in some complicated detective work.

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

When eleven-year-old Gregor and his two-year-old sister are pulled into a strange underground world, they trigger an epic battle involving men, bats, rats, cockroaches, and spiders while on a quest foretold by ancient prophecy.

When the Aldens go to the Pickering Natural History Museum to assist with the opening of a dinosaur exhibit, their work is hampered by a series of mysterious happenings.

The Alden children discover another mystery when the agree to help injured Mr. Yee tend to his plot in the community garden and find out that vegetables are going missing and plots are being vandalized.

The magic mirror has a crack and it sends Abby, Jonah, and Prince into the mixed up tale of Goldilocks and the Three Bears, and they soon find that Goldy is in need of a lot of gold to get her father out of jail, and so they find themselves negotiating between the Bears, who want honey, and Rumpelstiltskin, who just wants a friend or two--but King Ned is just plain greedy and somehow the children and Goldy's father have to escape from the king's jail,...

Scornful of his younger sister's fears, a young boy decides to explore a tunnel forcing her to go after him when he doesn't return.

Charlie, twelve, who has autism and obsessive compulsive disorder, must endure a cross-country trip with his siblings and a strange babysitter to visit their father, who will undergo brain surgery.

The Alden children suspect someone of trying to sabotage the local dog show.

When Peter feels he cannot put up with his baby sister Emily any longer, he puts her in his wagon and goes around the block to see if any of the neighbors want to buy her.