Dahl characterizes Matilda as a brilliant child early in the book, first contrasting her with very ordinary children, then exemplifying her precocious nature. Though a very little girl, Dahl sets her up to be the heroine early through the conflict with her parents. Matilda is morally superior to her parents, regarding both Mr. Wormwood’s behavior toward his daughter and his unethical work at the car dealership.
Dahl extends the ironic relationship between adults in need of a good punishment and the children willing to punish them to Miss Trunchbull and the kids at Crunchem Hall Primary School. The name of the school itself reflects Miss Trunchbull’s character, as “Crunchem,” when spoken aloud, sounds like “crunch them,” foreshadowing the headmistress’ desire to physically punish and harm the children. Matilda first hears of Miss Trunchbull’s cruel nature from a ten-year-old at the school named Hortensia. Hortensia tells Matilda and her friend, Lavender, of the tricks she played on Miss Trunchbull, inspiring Lavender to play a trick of her own. While on the playground, Lavender and Matilda witness Miss Trunchbull swing a girl around by her pigtails, then throw her several meters away, for no reason other than that the girl wore braids to school.
A few days later, Lavender punishes Miss Trunchbull for her cruelty by putting a newt in her water. Miss Trunchbull falsely accuses Matilda, which so angers the young girl that she channels her anger and brainpower through her eyes onto the glass of water, causing it to tip over and spill onto Miss Trunchbull.
Miss Honey, Matilda’s teacher, is a foil to Miss Trunchbull. Besides Mrs. Phelps, the librarian, Miss Honey is the only kind adult in Matilda’s life. The kindness of Miss Honey and Mrs. Phelps suggests a relationship between education and goodness, as further emphasized by the Wormwoods, who do not value education, and run an illegal car business, and Miss Trunchbull, who is not the headmistress to educate, but to punish children.
Matilda confides in Miss Honey about her powers, and in return, Miss Honey confides in Matilda about her relationship with Miss Trunchbull. This helps establish a strong relationship between the two, which grows every time they spend time together. If not for this strong relationship, Miss Honey would not have adopted Matilda, so Matilda would have had to move to Spain with her parents.
Though Matilda’s plan to scare Miss Trunchbull with the piece of chalk was designed to help Miss Honey, it actually liberated the entire school of the horrific woman.