The Heroes of Olympus

The second series of Percy Jackson books by Rick Riordan

The Blood of Olympus

Trials Of Apollo

What order should you read the "Trials Of Apollo" books? The brilliant fantasy series by Rick Riordan

The Hidden Oracle - The Trials of Apollo book 1
The Dark Prophecy - The Trials of Apollo book 2
The Burning Maze - The Trials Of Apollo book 3
The Tyrant’s Tomb - The Trials Of Apollo book 4
The Tower of Nero - The Trials Of Apollo book 5

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.)