Dinosaurs: A Nonfiction Companion to Magic Tree House #1: Dinosaurs Before Dark

Knights and Castles: A Nonfiction Companion to Magic Tree House #2: The Knight at Dawn

Pilgrims: A Nonfiction Companion to Magic Tree House #27: Thanksgiving on Thursday

American Revolution: A Nonfiction Companion to Magic Tree House #22: Revolutionary War on Wednesday

Penguins and Antarctica: A Nonfiction Companion to Magic Tree House Merlin Mission #12: Eve of the Emperor Penguin

Sea Monsters: A Nonfiction Companion to Magic Tree House Merlin Mission #11: Dark Day in the Deep Sea

Polar Bears and the Arctic: A Nonfiction Companion to Magic Tree House #12: Polar Bears Past Bedtime

Ghosts: A Nonfiction Companion to Magic Tree House Merlin Mission #14: A Good Night for Ghosts

Heroes for All Times: A Nonfiction Companion to Magic Tree House Merlin Mission #23: High Time for Heroes

Snakes and Other Reptiles: A Nonfiction Companion to Magic Tree House Merlin Mission #17: A Crazy Day with Cobras