| Author | Title |
|---|---|
| Jennifer O'Connell | Ten Timid Ghosts |
| Jane O'Connor | Nina, Nina, Ballerina |
| Jane O'Connor | Nina, Nina, Ballerina |
| Jane O'Connor | Fancy Nancy: The Dazzling Book Report |
| Jane O'Connor | Fancy Nancy |
| Susan O'Keefe | One Hungry Monster |
| Alexis O'Neill | The Recess Queen |
| Marin O'Neill | The Penguin Who Wanted To Be Different |
| Sarah O'Neill | Sleeping Animals |
| Sarah O'Neill | Sleeping Animals |
| Mary W. Olsen | Nice Try, Tooth Fairy |
| Kenneth Oppel | Sunwing |
| Shulamith Oppenheim | Fireflies For Nathan |
| Hiawyn Oram | In the Attic |
| Mary Pope Osborn | Vacation Under the Volcano |
| Mary Pope Osborn | Dolphins at Daybreak |
| Mary Pope Osborn | Pirates Past Noon |
| Mary Pope Osborne | Magic Tree House and Mummies in the Morning |
| Mary Pope Osborne | Magic Tree House-Polar Bears Past Bedtime |
| Kim Ostrow | Hello Kitty's Sneaky Peaky Mystery! |
| Kathryn Otashi | One |
| Annie Owen | Bumper to Bumper |
| Weldon Owen | Emergency Vehicles |