The Biggest House in the World (Knopf Children's Paperbacks)

This story-within-a-story about a snail who decides to have the biggest, most colorful shell of all gently teaches children the importance of humility. The proud snail's shell becomes too heavy for him to move, and that proves to be his undoing; the little snail hearing this tale from his father learns to be content with his tiny house, for it allows him to go wherever he pleases