Mrs. Frisby and the Rats of NIMH: Summary, Themes, and Characters

When teaching Mrs. Frisby and the Rats of NIMH or helping your child read it at home, it is often easier if you have a reminder of the plot. Here's a quick summary:

Mrs. Frisby, a mouse, is trying to take care of her children on her own since her husband was eaten by the farmer’s cat, Dragon. In the spring, Mrs. Frisby’s youngest son is ill, and he needs to be moved before the farmer starts plowing. But what can she do? She learns about the rats who live under the rose bush, and she decides to call on them for help. Soon she discovers that the rats knew her husband, and that they all used to be laboratory animals together. The rats agree to help Mrs. Frisby and a friendship starts. But then, the farmer decides to call an exterminator. Now, what will they do? This is not just a book about rats, mice, and life on a farm, it also explores the themes of friendship, loyalty, overcoming adversity, and heroism.

 Another important thing to touch on when teaching Mrs. Frisby and the Rats of NIMH is the universal themes in Robert C. O'Brien's book:

Friendship: Sometimes, the most unlikely of characters, people, or in this case, species can become friends. In this book, Mrs. Frisby doesn't think she can trust the rats, but then she has no choice but to turn to them. She discovers that her husband had befriended them and that she can also trust them. You and your students can discuss who are true friends in this novel and what friendship means. What does it mean to be a true friend?

Loyalty and Trust: Friendship, loyalty, and trust go hand-in-hand, and that's especially true in this middle-grade novel. Mrs. Frisby has to learn to trust the rats no matter what she thinks of them at the beginning. Nicodemus, the lead rat, decides to help Mrs. Frisby because of his loyalty to her husband. You can discuss with your students or your child what loyalty means to the characters in this book. You can also ask students about how the characters gain each other's trust.

Overcoming adversity: Mrs. Frisby is alone and must move her children to keep them safe from the farmer's plow. However, her son is ill, and she can't move him. Does she give up? No, she finds a way to overcome adversity and save her family. This theme can give students encouragement to try and do things they want or need to do even when it feels impossible to them.

Heroism: In today's society, we often call people "heroes" who don't have very "hero-like" behavior. So, the first thing to do when discussing this theme is to define what a hero truly is with your students or your child. Then talk about the characters in the story and see if they think any of them display hero-like behavior.

You can do different activities for Mrs. Frisby and the Rats of NIMH by focusing on the main characters in the story:

• Mrs. Frisby: She is the mother of the baby mice and one of the main characters of the story.
• Activity: ask students to write five adjectives that describe Mrs. Frisby such as worried, caring, mothering, smart, loving, and so on. When children have written five adjectives, ask them to find examples of Mrs. Frisby's behavior in the text that fit the adjectives.
• Timothy: He is the son of Mrs. Frisby who falls ill with pneumonia and can't be moved when it's time for the farmer to plow.
• Activity: Let your students or your child make a personal connection with Timothy and the story. Can they discuss with you a time when they were sick and had to miss something? You can also ask children to write or discuss how they feel when their parents or siblings are sick. Do they worry? Have they been upset because they had to miss something based on someone else's illness? Activities with the characters like this one with Timothy will help children comprehend the story.
• Nicodemus: Nicodemus is the leader of the rats. He is the one that tells Mrs. Frisby about the scientists and experiments at NIMH. Nicodemus and the rats agree to help Mrs. Frisby because he knew her husband when they were all at NIMH. This is the character trait of loyalty, and it is sometimes a difficult one for children to understand due to a lack of life experience. However, it is an important character trait in this story.
• Activity: ask students to draw posters or write poems and stories about loyalty. Study other people or characters from stories who are loyal. Ask students what loyalty means to them in their everyday lives. Talk about how people can be loyal to friends, family, a country, a business, and so on.

Some minor characters:

• Mr. Ages: An old and wise mouse who tries to help Mrs. Frisby by giving her medicine for Timothy.
• Johnathan Frisby: Mrs. Frisby's husband who escaped with Mr. Ages from the same laboratory as the rats.
• Jeremy: A young crow who Mrs. Frisby saves from the farmer's cat, Dragon.
• Farmer Fitzgibbon: The farmer who lives on the farm where Mrs. Frisby and the rats live.

Activities for Mrs. Frisby and the Rats of NIMH can focus on major and minor characters--students can even pick their favorite and create a display or poster on why this character is the best in the book.