Series beginning with A
- A Dinosaur Ate My Sister
- Abandon
- Abarat
- Abbey Mysteries
- Aberrations
- Abominators
- Above World
- Academy
- Accelerati Trilogy
- Accidental Adventures of Onion O'Brien
- Accidental Diary of B.U.G.
- Accidental Life of Jessie Jefferson
- Accidental Pirates
- Accidental Series
- Accidental Wizard
- Ace and the Animal Heroes
- Action Dogs
- Ada Lace Adventures
- Adam B
- Addison Cooke
- Adrian Mole
- Adventure Club
- Adventure Island
- Adventure Stories
- Adventuremice
- Adventurer's Guide
- Adventurers
- Adventures of Dog Man
- Adventures of Jack Brenin
- Adventures of Jewel Cardwell
- Adventures of John Blake
- Adventures of Miss Charlotte
- Adventures of Pug
- Adventures of Sam Witchall
- Adventures of Team Pom
- Adventures of the Steampunk Pirates
- Adventures of Titch and Mitch
- Adventures on Trains
- Adventures with Jeremy James
- After School Crime Club
- After School Detective Club
- After-School Superstars
- Agatha Oddly
- Agatha Parrot
- Age of the Five
- Agent 21 - Zac Darke
- Agent Alfie
- Agent Amelia
- Agent Asha
- Agent Weasel
- Agent Z
- Agent Zaiba Investigates
- Agents of S.U.I.T.
- Agents of the Wild
- Airborn
- Airhead Trilogy
- Ajay
- Al Capone
- Alana Dancing Star
- Alcatraz
- Aldo Moon
- Aldous Lexicon
- Aldrin Adams
- Alec Devlin
- Alex Neptune
- Alex Rider
- Alex Sparrow
- Alfie Bloom
- Alfie Small
- Alfie the Werewolf
- Ali Cross
- Alice
- Alice and Megan
- Alice Dent
- Alice Éclair, Spy Extraordinaire!
- Alice McKinley
- Alice McKinley Prequels
- Alice-Miranda
- Alien Adventures of Finn Caspian
- Alien in My Pocket
- Alien in the Jam Factory
- Alien Invaders - The Doom Vortex
- Alien Invaders - The Wrecking Zone
- Alien Next Door
- Alien Schoolboy
- Alien Superstar
- Alistair Grim's Odditorium
- All about Eve
- All American Girl
- All the Wrong Questions
- Allie Finkle's Rules for Girls
- Allie's Ghost Hunters
- Allies and Assassins
- Ally's World
- Alma
- Alpha Force
- Alternative Detective
- Amadans
- Amari
- Amazing Esme
- Amber Brown
- Amber Series
- Amelia Fang
- Amelia Jane
- Amos Daragon
- Amy Wild
- An Awfully Beastly Business
- Angel Academy
- Angel Trilogy
- Angel Wings
- Animal Ark
- Animal Ark Special
- Animal Magic
- Animal Rescue Agency
- Animal Rescue Centre
- Animal SOS
- Animal Stories
- Animorphs
- Anisha, Accidental Detective
- Anna Hibiscus
- Annals of the Western Shore
- Antigone Kingsley
- Apprentice Witch
- Araminta Spook
- Arc of a Scythe
- Arcadia Awakens
- Archibald Lox (e-book only)
- Archie
- Archie Greene
- Archived
- Arctic6
- Arena 13 Trilogy
- Aries Adventure
- Armouron
- Artemis Fowl
- Arthur
- Artichoke Hearts
- Artie Conan Doyle Mysteries
- Ascendance Trilogy
- Ash Mistry
- Ash Princess Trilogy
- Ashenpeake Island
- Ashes Triology
- Ashtown Burials
- Ask Amy Green
- Assassin's Curse
- Asterix
- Astonishing Life of Octavian Nothing
- Astronaut Girl
- AstroNuts
- Astrosaurs
- Astrosaurs Academy
- Astrotwins
- At the House of the Magician
- Atlantis
- Atomic!
- Atticus Claw
- Aubrey
- Aunt Severe
- Aurora Cycle
- Autumn Moonbeam
- Ava & Carol Detective Agency
- Avalon - Web of Magic
- Aveline Jones
- Avery McShane
- Avry of Kazan
- Awesome Animals - 1. Meerkats
- Awesome Animals - 2. Penguins
- Awesome Animals - 3. Pandas
- Awesome Animals - 4. Racoons
- Awesome Animals - 5. Koalas
- Awesome Animals - 6. Otters
- Awesome Animals - 7. Llamas
- Awesomely Austen
- Awkward
- AWOL
- Axel Storm
- Aziza's Secret Fairy Door