The Magic Tree House: Merlin Missions Books in Order, by Mary Pope Osborne

The Magic Tree House: Merlin Missions is a continuation of Mary Pope Osborne’s original Magic Tree House series.

In the Merlin Missions series, siblings Jack and Annie continue their adventures with the magical tree house, but with a new twist: they are now assisting the legendary wizard Merlin in various quests throughout time and space.

In these books, Jack and Annie receive missions from Merlin, who has enchanted the tree house to help them travel to different places and times. Their missions often involve helping people, solving problems, or overcoming challenges related to historical events, myths, and legends.

Here is the Magic Tree House: Merlin Missions Series in Order

Christmas in Camelot (2001)
Haunted Castle on Hallow’s Eve (2003)
Summer of the Sea Serpent (2004)
Winter of the Ice Wizard (2004)
Carnival At Candlelight (2005)
Season of the Sandstorms (2005)
Night of the New Magicians (2006)
Blizzard of the Blue Moon (2006)
Dragon of the Red Dawn (2007)
Monday With a Mad Genius (2007)
Dark Day in the Deep Sea (2008)
Eve of the Emperor Penguin (2008)
Moonlight on the Magic Flute (2009)
A Good Night for Ghosts (2009)
Leprechaun in Late Winter (2009)
A Ghost Tale for Christmas Time (2010)
A Crazy Day with Cobras (2011)
Dogs in the Dead of Night (2011)
Abe Lincoln at Last! (2011)
A Perfect Time for Pandas (2012)
Stallion by Starlight (2013)
Hurry Up, Houdini! (2013)
High Time for Heroes (2014)
Soccer on Sunday (2014)
Shadow of the Shark (2015)
Balto of the Blue Dawn (2016)
Night of the Ninth Dragon (2016)