The 13 Storey Treehouse

The kids book series by Andy Griffiths

The 13-Storey Treehouse - The Treehouse Books - Book 1
The 26-Storey Treehouse - The Treehouse Books - Book 2
The 39-Storey Treehouse - The Treehouse Books - Book 3
The 52-Storey Treehouse - The Treehouse Books - Book 4
The 65-Storey Treehouse - The Treehouse Books - Book 5
The 78-Storey Treehouse - The Treehouse Books - Book 6
The 91-Storey Treehouse - The Treehouse Books - Book 7
The 104-Storey Treehouse - The Treehouse Books - Book 8
The 117-Storey Treehouse - The Treehouse Books - Book 9

Tom Gates

The brilliant childrens' book series by Liz Pichon

Yes! No (Maybe...)
Top of the Class (Nearly)
Tom Gates: Super Good Skills (Almost...)
DogZombies Rule (for Now)
Family, Friends and Furry Creatures - Tom Gates book 12
Tom Gates - Book 13 - Epic Adventure (Kind Of)
Tom Gates: Biscuits, Bands and Very Big Plans
Tom Gates book 15 - What Monster?
Tom Gates book 16 - Tom Gates: Mega Make and Do (and Stories Too!)
Tom Gates book 17 - Spectacular School Trip (Really.)

Sherlock Holmes

If you've never read a Sherlock Holmes book before, I recommend starting with one of the selections, like The Adventures of Sherlock Holmes

Sherlock Holmes - A Study in Scarlet
Sherlock Holmes - The Sign of Four
Sherlock Holmes - The Adventures of Sherlock Holmes
Sherlock Holmes - The Memoirs of Sherlock Holmes
Sherlock Holmes - The Hound of the Baskervilles
Sherlock Holmes - The Return of Sherlock Holmes
Sherlock Holmes - The Valley of Fear
Sherlock Holmes - His Last Bow
Sherlock Holmes - The Casebook of Sherlock Holmes

The Underland Chronicles

The fantasy series by Susanne Collins, author of The Hunger Games

The Underland Chronicles book 1 - Gregor the Overlander
The Underland Chronicles book 2 - Gregor and the Prophecy of Bane
The Underland Chronicles book 3 - Gregor and the Curse of the Warmbloods
The Underland Chronicles book 4 - Gregor and the Marks of Secret
The Underland Chronicles book 5 - Gregor and the Code of Claw