| Title | Missing Word | Original Publishing Year |
| The Secret of the Old ____ | |
| The Hidden ____ | |
| The Bungalow ____ | |
| The Mystery at ____ Inn | |
| The Secret of ____ Ranch | |
| The Secret of ____ Gate Farm | |
| The ____ in the Diary | |
| Nancy's Mysterious ____ | |
| The Sign of the ____ Candles | |
| The ____ to Larkspur Lane | |
| The Clue of the Broken ____ | |
| The Message in the Hollow ____ | |
| The Mystery of the ____ Charm | |
| The ____ Statue | |
| The Haunted ____ | |
| The Clue of the ____ Heels | |
| The Mystery of the ____-Bound Trunk | |
| The Mystery at the Moss-Covered ____ | |
| The ____ of the Missing Map | |
| The Clue in the ____ Box | |
| The Secret in the ____ Attic | |
| The Clue in the ____ Wall | |
| The Mystery of the ____ Bell | |
| The Clue in the Old ____ | |
| The ____ of Blackwood Hall | |
| The Clue of the ____ Chimney | |
| The Secret of the Wooden ____ | |
| The Clue of the ____ Keys | |