The Magic City (novel)

He has trouble adjusting at first, thrown into the world different from his previous life and abandoned by his sister while she is on her honeymoon.

To entertain himself he builds a giant model city from things around the house: game pieces, books, blocks, bowls, etc.

Kill the Dragon: assigned, done by Philip, while Lucy played the role of Princess in distress.

Slaying the Lions in the Desert: shared task, completed before 3, pronounced a deed after the fact.

Devise a Means of Keeping the Great Sloth Awake and Busy: assigned task, shared effort.

Temple of the Great Sloth, illustration by H. R. Millar