"Miss Nelson" is a children's book written by Harry Allard and illustrated by James Marshall. It tells the story of a kind and gentle teacher, Miss Nelson, who struggles to manage her unruly class. The students often misbehave and take advantage of her sweetness, leading to chaos in the classroom. To teach her students a lesson, Miss Nelson mysteriously disappears, and a strict substitute teacher named Miss Viola Swamp takes her place. The children quickly realize how much they miss Miss Nelson's caring nature and begin to appreciate her once she returns, learning the importance of respect and kindness.