Miss Viola Swamp

Miss Viola Swamp is known as "the meanest substitute teacher in the whole world", in three children's picture books by Harry Allard with illustrations by James Marshall: Miss Nelson is Missing! (1977), Miss Nelson is Back (1982), and Miss Nelson Has a Field Day (1985).

Miss Nelson is a grade-school teacher whose students constantly take advantage of her nice nature. After their constant misbehaving and rudeness, and their refusal to learn, Miss Nelson determines something has to be done. But then one day, she does not come to school. "Now we can really act up," yells one of the students (Allard, 8). However, before they get the chance to make mischief, a substitute, Miss Viola Swamp, shows up. Swamp is a strict disciplinarian and gives the students significantly more school work than Miss Nelson ever did. The contrast between the two teachers is so great that the students actively go looking for Miss Nelson and make unlikely conjectures about what may have happened to her, including some students who go so far as to fill out a missing person report with the local police. After many days of tyranny under Miss Swamp, Miss Nelson returns to class and the children rejoice, now being more respectful of her. At the end of the book, it is revealed that Miss Viola Swamp was Miss Nelson in disguise, and a police detective has called off his search for Miss Nelson and will now look for this enigmatic Miss Swamp.

After Miss Nelson informs the class that she will be absent for a week, the class fears that they have Miss Viola Swamp as their substitute after a bigger kid from another class warns them about her (suggesting this is a different class than in the first book or that this is a kid from the first book, now older and in a different grade.). Their fears are momentarily relieved when Mr. Blandsworth, the school principal, announces he will substitute. However, Mr. Blandsworth gives extremely boring lectures and so three of the students plan a scheme to disguise themselves as Miss Nelson in an attempt to lead Mr. Blandsworth into thinking that his services as a substitute teacher are no longer necessary. This works, and all the kids celebrate their lawlessness by seeing The Monster that Ate Chicago and pigging out at Lulu's. However, they are unknowingly spotted by Miss Nelson, and the kids are later horrified to see the return of Viola Swamp! Once order is reestablished by Miss Swamp, Miss Nelson returns to class.