- Polar bears and the Arctic, a nonfiction companion to polar bears past bedtime, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Lions at lunchtime, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Revolutionary War on Wednesday, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Dog heroes, a nonfiction companion to Magic tree house #46: Dogs in the dead of night, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Good morning, gorillas, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A ghost tale for Christmas time, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Tigers at twilight, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Leonardo da Vinci, a nonfiction companion to Monday with a mad genius, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Stallion by starlight, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Ancient Rome and Pompeii, a nonfiction companion to Vacation under the volcano, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- High tide in Hawaii, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Ghosts, a nonfiction companion to a good night for ghosts, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Tsunamis and other natural disasters, a nonfiction companion to High tide in Hawaii, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Soccer on Sunday, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A crazy day with cobras, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Earthquake in the early morning, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Heroes for all times, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Dark day in the deep sea, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Twister on Tuesday, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Eve of the Emperor penguin, by Mary Pope Osborne ; [illustrations by Sal Murdocca]
- Tonight on the Titanic, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Mummies in the morning, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Afternoon on the Amazon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Dinosaurs, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Summer of the sea serpent, Mary Pope Osborne ; illustrated by Sal Murdocca
- Leprechauns and Irish folklore, a nonfiction companion to Leprechaun in late winter, Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Hurry up, Houdini!, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Dinosaurs before dark, Mary Pope Osborne ; illustrated by Sal Murdocca
- Dingoes at dinnertime, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A perfect time for pandas, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Knights and castles, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Night of the Ninjas, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Day of the Dragon King, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A good night for ghosts, Mary Pope Osborne ; illustrated by Sal Murdocca
- Monday with a mad genius, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Season of the sandstorms, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Christmas in Camelot, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Blizzard of the blue moon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Moonlight on the magic flute, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Night of the ninth dragon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Civil War on Sunday, [Mary Pope Osborne ; illustrated by Sal Murdocca]
- Mummies and pyramids, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Vacation under the volcano, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Midnight on the moon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Ninjas and samurai, a nonfiction companion to Magic tree house #5 : Night of the ninjas, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Dogs in the dead of night, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Carnival at candlelight, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Buffalo before breakfast, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Night of the new magicians, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Sea monsters, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca