Collins, Suzanne. Gregor the Overlander. (Underland Chronicles, bk.1)
11-year old Gregor and his 2-year old sister enter into a mysterious underground world where they embark on a quest to find their missing father.
Durst, Sarah Beth. Into the Wild.
Julie's mother, Rapunzel, escaped her fairy tale, but when "the wild" takes over the entire town, Julie must prevent everyone from being trapped in a fairy tale forever.
Gordon, Roderick. Tunnels.
Will Burrows and his friend Chester must venture into an underground world with cruel and evil inhabitants in order to rescue his father.
Kladstrup, Kristin. The Book of Story Beginnings.
After moving to Iowa with her family, Lucy finds a notebook that brings stories to life. When Lucy writes in the notebook, her story adventures lead her to her great uncle, who disappeared as a boy.