- Penguins and Antarctica, a nonfiction companion to Eve of the emperor penguin, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Buffalo before breakfast, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Leprechaun in late winter, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Titanic, a nonfiction companion to Tonight on the Titanic, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Magic tricks from the tree house, a fun companion to Magic Tree House #50 : hurry up, Houdini!, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Dingoes at dinnertime, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Horse heroes, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Tigers at twilight, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Mummies and pyramids, a nonfiction companion to Mummies in the morning, by Will Osborne and 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
- Dolphins and sharks, a nonfiction companion to Dolphins at daybreak, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Eve of the Emperor penguin, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A big day for baseball, by Mary Pope Osborne ; cover illustration by Sal Murdocca ; interior illustrations by Ag Ford
- Striding slippers, adapted from an Udmurt tale by Mirra Ginsburg ; pictures by Sal Murdocca
- Dinosaurs, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Sunset of the sabertooth, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Good morning, gorillas, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Monday with a mad genius, by Mary Pope Osborne ; illustrated by Sal Murdocca, 38
- Leprechauns and Irish folklore, a nonfiction companion to Leprechaun in late winter, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Dolphins at daybreak, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Snakes and other reptiles, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Mummies in the morning, by Mary Pope Osborne ; illustrated by Sal Murdocca
- American revolution, a nonfiction companion to Revolutionary War on Wednesday, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- High time for heroes, Mary Pope Osborne ; illustrated by Sal Murdocca
- The knight at dawn, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Abe Lincoln at last!, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Sea monsters, by Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Shadow of the shark, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Dinosaurios al atardecer, Mary Pope Osborne ; ilustrado por Sal Murdocca ; traducido por Marcela Brovelli
- Soccer, a nonfiction companion to Magic Tree House Merlin Mission #24 Soccer on Sunday, Mary Pope Osborne and Natalie Pope Boyce ; illustrated by Sal Murdocca
- Afternoon on the Amazon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Revolutionary War on Wednesday, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Space, by Will Osborne and Mary Pope Osborne ; illustrated by Sal Murdocca
- Dragon of the red dawn, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Night of the new magicians, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Dinosaurs before dark, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Hurry up, Houdini!, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Lions at lunchtime, by Mary Pope Osborne ; illustrated by Sal Murdocca
- 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
- Danger in the darkest hour, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Carnival at candlelight, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Double trouble in Walla Walla, by Andrew Clements ; illustrated by Sal Murdocca
- Midnight on the moon, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Haunted castle on Hallows Eve, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Stage fright on a summer night, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Civil War on Sunday, [Mary Pope Osborne ; illustrated by Sal Murdocca]
- Season of the sandstorms, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A perfect time for pandas, by Mary Pope Osborne ; illustrated by Sal Murdocca
- Summer of the sea serpent, by Mary Pope Osborne ; illustrated by Sal Murdocca
- A ghost tale for Christmas time, by Mary Pope Osborne ; illustrated by Sal Murdocca