Night of the New Magicians (Magic Tree House: Merlin Missions Book 7)

Blizzard of the Blue Moon (Magic Tree House (R) Merlin Mission Book 8)

Monday with a Mad Genius (Magic Tree House (R) Merlin Mission Book 10)

Dragon of the Red Dawn (Magic Tree House (R) Merlin Mission Book 9)

Dark Day in the Deep Sea (Magic Tree House (R) Merlin Mission Book 11)

Eve of the Emperor Penguin (Magic Tree House (R) Merlin Mission Book 12)

Moonlight on the Magic Flute (Magic Tree House (R) Merlin Mission Book 13)