The Detective’s Assistant by Kate Hannigan

The Detective's Assistant Cover

Book Info

Grade Level
Elementary School, Middle School
STEM Concepts
Engineering, Cryptography, Logical/Mathematical/Computational Thinking

Based on the extraordinary true story of America’s first female detective, Kate Warne, this fast-paced adventure is full of feats of daring and danger, bold action, and newfound courage.

When orphaned eleven-year-old Nell Warne arrives in Chicago, she is shocked to find that her long-lost aunt is a detective working for the famous Pinkerton’s National Detective agency! With nation-changing events simmering in the background as Abraham Lincoln heads for the White House, Aunt Kate is working on the biggest case of her life, and Nell quickly makes herself indispensable by cracking codes, wearing disguises, and spying on nefarious criminals. But can she also solve the case of what really happened on the night her best friend disappeared?

Source: Little, Brown Young Readers


The State of Mont Rose's Bowels

We interviewed local historian Clint Cargile about DeKalb and Sycamore history, and he taught us the importance of social history. The day-to-day history of average people can teach a lot about a time period, just as much as the bigger picture history found in many textbooks.

Field Trip Overview

The year is 1860, and President-Elect Abraham Lincoln is making his way to his inauguration. Angry, the southern sympathizers plot to stop him from reaching his destination. It’s up to you to collect the clues, find the plotters, and save the president!

The Costume Makes the Character

In The Detective’s Assistant, Nell and Kate Warne have to dress in disguises in order to worm out the suspects. We spoke with Professor Jeremy Floyd about how costumes help complete a character.

Kate Warne: Pinkerton's First Female Detective

Author Kate Hannigan talks about what inspired her to research and write about Pinkerton’s first female detective: Kate Warne.

Researching the Detective's Assistant with Kate Hannigan

Author Kate Hannigan shares her tips for researching historical fiction.

Author Kate Hannigan on the STEM Read Podcast

Listen to our interview with Kate Hannigan from the STEM Read Podcast.


The STEM Read Experience Based on the Book

Click the image below to access pictures from The Detective’s Assistant: The STEM Read Experience.


STEM Read’s Suggested Lincoln

Are you looking to book a Lincoln for your event? STEM Read recommends actor Kevin Wood.


Idea Sparks and Mini Lessons

These questions, prompts, and short activities provide quick ways to inspire interest and explore the STEAM concepts related to the book. Idea Sparks and Mini Lessons can also be used for differentiation and to foster new ideas of your own.

Download Lesson Plan

Beat the Heat

Nell often mentioned the extreme heat in the South where they had no air conditioning at the time. People had to come up with other ways to stay cool. In this PBL challenge, students will develop a driving question about heat. Then they will research the issue and come up with a way to resolve it.

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Detectives Need Math, Too

Kate Warne and Nell would have needed to use math in their everyday lives while being detectives. In this math challenge, students first solve a set of practice problems. Next, students develop a math problem that may have come up in Nell and Kate’s adventures.

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Donning a Disguise

Nell and Aunt Kate often had to don a disguise and pretend to be another person. Aunt Kate was always reminding Nell to “stay in character.” In this challenge, students will design a disguise for one member of their group. Students will also list some characteristics of the person wearing the disguise.

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Home, Home on the Train

When trains were the main mode of transportation, some wealthy people and companies had custom designed railroad cars. In this multi-faceted lesson, students will design a custom railroad car for Pinkerton’s National Detective Agency.

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Invisible Messages

Hidden messages come in handy when trying to conceal information. Using invisible ink could add even another layer to a code being used. Many times in the story messages needed to be kept from prying eyes. In this science investigation, students will determine which type of substance is best for writing with invisible ink.

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Secret Ciphers and Codes

Ciphers were an important part of the action in The Detective’s Assistant. Nell used codes to communicate with her friend. Civil War era spies used ciphers and codes to send messages to plot and plan. In this exploration activity, students will learn about the Caesar cipher and create one of their own. As they decipher and encrypt messages in Morse code, students will also get a simulated experience of what it was like to be a telegraph operator.

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STEM Read Cipher Disk

The Case of the Noisy Boots

Nell’s boots were noisy. If they were quieter, she could more easily spy on people or listen in on secret conversations. If they were louder, she might seem like a much bigger person, which could scare off an enemy. In this engineering challenge, students try to make a boot sound quieter or louder, using a variety of materials.

Download Lesson Plan

Loved The Detective’s Assistant by Kate Hannigan? Check out our list of read alikes!

About the Author

Kate Hannigan

Chicago author Kate Hannigan writes fiction and nonfiction for young readers. A former newspaper journalist at The San Francisco Chronicle and The Dallas Morning News, Kate loves digging up facts and snooping into history for good stories to tell. That’s why her house is lined with stacks of books about remarkable people who lived fascinating lives.

Kate’s historical fiction “The Detective’s Assistant” (Little, Brown Books for Young Readers) was inspired by America’s first woman detective, Kate Warne, who was hired by legendary detective Allan Pinkerton in 1856 in downtown Chicago. It received the Golden Kite Award for best middle-grade novel, was named a Booklist Editors’ Choice selection, Nerdy Book Club Award Winner, Bank Street College Best Children’s Book, selected for the ALA Amelia Bloomer Project List for Feminist Books, and was named A Mighty Girl Top Books for Tweens and Teens pick. It also was named a Chicago Public Library Best Book and Illinois READS State List selection, and was optioned for film. Kate’s humorous cooking-caper series for younger readers, “Cupcake Cousins,” was also named to Illinois READS and Chicago Public Library “Best of the Best” lists. Her latest title, the picture book biography “A Lady Has the Floor: Belva Lockwood Speaks Out for Women’s Rights” spotlights barrier-breaker and early suffragette Belva Lockwood, who fought for the rights of women in classrooms, courtrooms, and the ballot box. It was named a Junior Library Guild Selection and received four starred reviews.

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