- Open If You Dare
- Operation Frog Effect
- Operation Pucker Up
- Operation Stay in England
- Operation Tiger
- POR DENTRO DA OPERAÇÃO PALMARES
- Ophelia and the Marvelous Boy
- Opowieści o uczuciach
- Opposite Island
- Oracles of Delphi Keep
- Orchestra in Our Brain
- Order of the Majestic
- Os miseráveis
- Oscar Season
- Other Boys
- Outcast
- Outcasts United
- Outrageously Alice
- Outside Beauty
- Outside in the Snow with Buster and Friends. A Sight Words Picture Book
- Over & Out #10
- Over the Moon
- Overcoming My Mother's Addictions
- Overcoming The Storms Of Life
- Overload
- Overworld in Flames
- Ovily Pumpkin
- Own Your Period
- Ozzie, the Courageous Otter