What do you think?
Rate this book
Sir Cumference #3
Sir Cumference and the Great Knight of Angleland
Join Sir Cumference, Lady Di of Ameter, and their son Radius for wordplay, puns, and problem solving in this angle-packed math adventure. In the third installment of the beloved Sir Cumference series, Radius must prove himself on his quest for knighthood by rescuing a king. Sent off with the family medallion for luck, Radius dodges dangers and dragons. The ultimate challenge lies in a mysterious castle with a maze of many angles.
32 pages, Paperback
First published January 1, 2001
3 people are currently reading
468 people want to read
About the author
Cindy Neuschwander
39 books55 followersCindy Neuschwander is a native Californian, born in San Diego, CA. Her father was a naval officer and later a high school teacher and her mother was a homemaker. She has one younger brother.
Cindy graduated with a BA in International Studies from Willamette University and earned an MA from Stanford University. She has taught all grades in elementary school as well as high school.
Cindy began writing books in 1994. She had used math literature with her own classes in the early 1990’s and liked the way students responded to it. She wanted to use more of these books but found there were not many available so she started writing some of her own. Her books are published by Charlesbridge, Henry Holt, and Scholastic. She usually writes one book a year.
When she is not teaching or writing, Cindy enjoys spending time with her family. She has been married to her husband, Bruce, for over 30 years. Their older son, Tim, is a medical doctor working in orthopedic research. Their younger son, Seth, is a college student training to become a firefighter. Cindy and Bruce own three dogs; two Dalmatians and a Gordon Setter. Cindy loves to travel, bike ride, and swim. She and her family are Christians who are active in their local church.
Cindy graduated with a BA in International Studies from Willamette University and earned an MA from Stanford University. She has taught all grades in elementary school as well as high school.
Cindy began writing books in 1994. She had used math literature with her own classes in the early 1990’s and liked the way students responded to it. She wanted to use more of these books but found there were not many available so she started writing some of her own. Her books are published by Charlesbridge, Henry Holt, and Scholastic. She usually writes one book a year.
When she is not teaching or writing, Cindy enjoys spending time with her family. She has been married to her husband, Bruce, for over 30 years. Their older son, Tim, is a medical doctor working in orthopedic research. Their younger son, Seth, is a college student training to become a firefighter. Cindy and Bruce own three dogs; two Dalmatians and a Gordon Setter. Cindy loves to travel, bike ride, and swim. She and her family are Christians who are active in their local church.
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 - 30 of 92 reviews
December 27, 2018
Sir Cumference is a series of entertaining, clever, and imaginative medieval fantasy tales set in a world full of fun geometry-based names and lands. The reader follows the adventure of each book and discovers new math concepts along with the knights and ladies in the stories - and sometimes dragons. I've always loved a good picture book, and I still do - and these books are a wonderful example of a quality picture book. I've enjoyed Sir Cumference immensely in both childhood and adulthood.
Each book is engaging and well-written, with endearing and clever characters, exciting adventures, and humor throughout. I laugh at the puns and plays on words and at the hilarious situations the characters often go through. I'm amazed at the loveliness of the illustrations, which - like the text - are colorful, funny, exciting, and imaginative, as well as beautifully painted on actual canvas, with gorgeous lighting and color.
And the math concepts presented in the text are humourously, clearly, and simply explained, while still retaining complex and sophisticated information of basic geometry and sometimes other areas of math. And in the context of a fun story, they're easy to remember and recall. A very young child can understand the explanation of the basic concept, the full explanation can aid the learning of an older student, and teens and adults can enjoy the clever books just as much.
I'm good at math, but it's never come easily to me, as it does for my siblings. I struggle to learn and understand math concepts when I can't understand the why and how behind them. Even as a teen and adult, and as a child, reading Sir Cumference helped give me that brilliant light-bulb moment of finally understanding why the equation to find the circumference or area of a circle is the way it is, and works the way it does. The books break these concepts down and show them in concrete, tangible ways, rather than only abstract, nebulous numbers and equations. This way, it's easy to understand how the equation works to produce the number, instead of being unreachable and impossible to wrap one's mind around. Weaving the math into the context of an imaginative story with relatable characters also helps so much, because that's how my mind and imagination engage best with information. If I get the chance to follow in my parents' steps and homeschool my own kids someday, or even if I don't, I will definitely be using these books to teach my future children, if I have any.
I first read the Sir Cumference series as an elementary school-aged child, and I've loved them ever since. The stories have always made me laugh and captured my imagination. It's been a few years since I've read them, and upon rereading the series, I'm pleased to find that the books are are just as wonderful and quality now that I'm an adult and a writer. I was also overjoyed to recently discover the existence of more Sir Cumference sequels that I'd wished for for many years.
I grew up with the first four SirSir Cumference books, and they're special to me, but I enjoyed a couple of the new ones just as much. The first four books in the series are best read in order, but some of the later books were not published chronologically, and they can be read in any order after the first book. For instance, The Isle of Immeter can be read in any order after the first two books, but it should be read before The Viking's Map, since it introduces a new female protagonist. My favorite books in the series are definitely the ones featuring Sir Cumference's son Radius as the main character - the ones I grew up on, and also the slightly newer books I read more recently that follow both Radius and his female cousin Per of Immeter.
The Sir Cumference books are full of sweet characters, exciting tales, adventure, entertaining humor, learning, and more. All this is contained in a short picture book - no small feat! I highly recommend the Sir Cumference series to people of all ages who enjoy a clever and fun story, especially to teachers and homeschoolers for teaching math in an entertaining and engaging manner.
Each book is engaging and well-written, with endearing and clever characters, exciting adventures, and humor throughout. I laugh at the puns and plays on words and at the hilarious situations the characters often go through. I'm amazed at the loveliness of the illustrations, which - like the text - are colorful, funny, exciting, and imaginative, as well as beautifully painted on actual canvas, with gorgeous lighting and color.
And the math concepts presented in the text are humourously, clearly, and simply explained, while still retaining complex and sophisticated information of basic geometry and sometimes other areas of math. And in the context of a fun story, they're easy to remember and recall. A very young child can understand the explanation of the basic concept, the full explanation can aid the learning of an older student, and teens and adults can enjoy the clever books just as much.
I'm good at math, but it's never come easily to me, as it does for my siblings. I struggle to learn and understand math concepts when I can't understand the why and how behind them. Even as a teen and adult, and as a child, reading Sir Cumference helped give me that brilliant light-bulb moment of finally understanding why the equation to find the circumference or area of a circle is the way it is, and works the way it does. The books break these concepts down and show them in concrete, tangible ways, rather than only abstract, nebulous numbers and equations. This way, it's easy to understand how the equation works to produce the number, instead of being unreachable and impossible to wrap one's mind around. Weaving the math into the context of an imaginative story with relatable characters also helps so much, because that's how my mind and imagination engage best with information. If I get the chance to follow in my parents' steps and homeschool my own kids someday, or even if I don't, I will definitely be using these books to teach my future children, if I have any.
I first read the Sir Cumference series as an elementary school-aged child, and I've loved them ever since. The stories have always made me laugh and captured my imagination. It's been a few years since I've read them, and upon rereading the series, I'm pleased to find that the books are are just as wonderful and quality now that I'm an adult and a writer. I was also overjoyed to recently discover the existence of more Sir Cumference sequels that I'd wished for for many years.
I grew up with the first four SirSir Cumference books, and they're special to me, but I enjoyed a couple of the new ones just as much. The first four books in the series are best read in order, but some of the later books were not published chronologically, and they can be read in any order after the first book. For instance, The Isle of Immeter can be read in any order after the first two books, but it should be read before The Viking's Map, since it introduces a new female protagonist. My favorite books in the series are definitely the ones featuring Sir Cumference's son Radius as the main character - the ones I grew up on, and also the slightly newer books I read more recently that follow both Radius and his female cousin Per of Immeter.
The Sir Cumference books are full of sweet characters, exciting tales, adventure, entertaining humor, learning, and more. All this is contained in a short picture book - no small feat! I highly recommend the Sir Cumference series to people of all ages who enjoy a clever and fun story, especially to teachers and homeschoolers for teaching math in an entertaining and engaging manner.
September 6, 2012
My intent with this site is not to give reviews. But it is really difficult to stick to principle when confronted with something this bad. Now, I liked the original Sir Cumference book. I am not opposed to trying to mix mirth with math. But, in place of mirth, this book has a torturous plot designed only to allow the main character to talk about "a cute" angle (get it?), and instead of math, there's... I don't know, it's like some backwards vocabulary lesson, whereby I'm supposed to remember the word for parallel lines because a "King" named, coincidentally, Lell, happens to own two dragons whose tails extend in the same direction over a moat - are you buying this?
There is actually something noteworthy here, in that it seems to give an indication of what the author considers mathematics to be, namely memorizing things that don't make any sense. I'm not holding her personally responsible, but I object. I don't consider any of the "facts" encountered herein to augment the reader's knowledge of mathematics. The approach to angle measure is just, well, sort of orthogonal to the concept of measuring angles, and at any rate I don't need a protractor to tell me when an angle is "Small".
(from my not-really-a-blog at https://sites.google.com/site/molnarm...)
There is actually something noteworthy here, in that it seems to give an indication of what the author considers mathematics to be, namely memorizing things that don't make any sense. I'm not holding her personally responsible, but I object. I don't consider any of the "facts" encountered herein to augment the reader's knowledge of mathematics. The approach to angle measure is just, well, sort of orthogonal to the concept of measuring angles, and at any rate I don't need a protractor to tell me when an angle is "Small".
(from my not-really-a-blog at https://sites.google.com/site/molnarm...)
April 16, 2021
My 9yo still loves this series of picture books, and we're working our way through them as they become available at the library. He chuckles every time he gets one of the little vocabulary puns. My only wish with this one was that they would have named the protractor. The book ended with Radius still calling it "the medallion." But maybe that will be explained later in the series?
October 30, 2022
As a Mathematics teacher I find Ms. Neuschwander's books entertaining and good teaching tools for introducing concepts to young learners.
September 28, 2017
Author: Cindy Neuschwander
Illustrator: Wayne Geehan
First published: 2001
Length: 32 pages
Defines right, obtuse, acute and straight angles.
Defines parallel lines.
Sir Cumference:
Book 1 Sir Cumference and the First Round Table
Book 2 Sir Cumference and the Dragon of Pi
Book 3 Sir Cumference and the Great Knight of Angleland
Book 4 Sir Cumference and the Sword in the Cone
Book 5 Sir Cumference and the Isle of Immeter
Book 6 Sir Cumference and all the King's Tens
Book 7 Sir Cumference and the Viking's Map
Book 8 Sir Cumference and the Off-the-Charts Desserts
Book 9 Sir Cumference and the Roundabout Battle
(ISBN 9781570911699)
-CR-
Illustrator: Wayne Geehan
First published: 2001
Length: 32 pages
Defines right, obtuse, acute and straight angles.
Defines parallel lines.
Sir Cumference:
Book 1 Sir Cumference and the First Round Table
Book 2 Sir Cumference and the Dragon of Pi
Book 3 Sir Cumference and the Great Knight of Angleland
Book 4 Sir Cumference and the Sword in the Cone
Book 5 Sir Cumference and the Isle of Immeter
Book 6 Sir Cumference and all the King's Tens
Book 7 Sir Cumference and the Viking's Map
Book 8 Sir Cumference and the Off-the-Charts Desserts
Book 9 Sir Cumference and the Roundabout Battle
(ISBN 9781570911699)
-CR-
April 11, 2013
The Sir Cumference series of books is AWESOME for students in older grades (3rd-5th). This specific one can be used in the classroom to teach about angle and the use of a protractor. Radius, Sir Cumference's son, sets out on an adventure to rescue the King. A protractor (the circular medallion) was given to Radius by his father and his mother, Lady Di of Ameter to aid him in examining every angle along the way. As you read, you may provide your students with their own protractor so that they can follow along.
December 25, 2017
This felt pretty forced and artificial. It starts by introducing right angles and straight angles, and then there's a family heirloom protractor that no one understands. After that it introduces obtuse and acute (but not reflex) angles, and Radius figures out the degree measures corresponding to all these angles.
October 4, 2016
Ellie and mom rates 4 stars, Jacob 3 stars. Read for CC2...krb 10/3/16
May 11, 2023
This book could be such a fun way to get students interested in learning geometry because terms and facts are taught in the form of an adventure story that takes place in medieval times and is filled with geometry puns. The lovely illustrations add to the excitement and seem to transport the reader to the time period of the story. The story is about a young man named Radius who wants to be a knight. He embarks on a quest to save a missing king, and along the way he must encounter various kinds of angles. Readers will learn about angle measurements and various other geometric concepts as Radius discovers and names them. Included with the book is a protractor like the one that Radius uses to measure angles in the story so that kids can measure angles for themselves.
September 21, 2017
Summary
Sir cumference and his friends are all named after different math properties, and their action display those qualities. They go on adventures that help teach each property in a fun way.
Evaluation
Very creative book with pictures that help support the words written down on the page. These pictures offer great context clues to struggling readers looking for a hint.
Teaching Ideas
This book is both a great study tool to have in you classroom library and a fun story to read to your class to review circumference and other similar properties. This was read in my 5th grade placement and the children greatly enjoyed the book.
June 3, 2021
This is a series of different books that tie into math concepts. The characters are named after different math concepts which is a great way to introduce new vocabulary. It is a wonderful example of how to integrate ELA and math.
These stories could be a great introduction to a math lesson. They could be used to introduce a concept or review something that has been being studied.
This book addresses protractors, angles, including straight, right etc. It introduces characters like Sir D’Grees and the Mountains of Obtuse.
With this story you could have students create their own measurement riddle to have others solve.
Grades: any covering the skills addressed!
These stories could be a great introduction to a math lesson. They could be used to introduce a concept or review something that has been being studied.
This book addresses protractors, angles, including straight, right etc. It introduces characters like Sir D’Grees and the Mountains of Obtuse.
With this story you could have students create their own measurement riddle to have others solve.
Grades: any covering the skills addressed!
April 21, 2020
King Lell is missing and someone needs to search for him. Young Radius, the squire, goes in search of him. Using his knowledge of angles, the young squire solves the riddle to the King's location.
This clever book introduces math terms in a concrete way for students. Some of these terms are diameter, circumference, obtuse, and acute. This would be a great book to read aloud in the 1st and 2nd grades when starting a unit on geometry (specifically about the circle). It would even be helpful to introduce for older students to give them a visual to think back on for their math terms.
This clever book introduces math terms in a concrete way for students. Some of these terms are diameter, circumference, obtuse, and acute. This would be a great book to read aloud in the 1st and 2nd grades when starting a unit on geometry (specifically about the circle). It would even be helpful to introduce for older students to give them a visual to think back on for their math terms.
October 9, 2021
Another fun math adventure in the Sir Cumference series. Sir Cumference’s son, Radius, is on a quest to rescue a missing king, and his family’s “medallion” (a protractor) helps him to find his way through a fearsome labyrinth. My library’s copy of the book has a “medallion”-protractor tucked in the back of the book (it miraculously hasn’t been lost), but there isn’t anything in the book where you would specifically need to use a protractor. I assume it’s just for playing around and measuring angles on your own. I’ll be using this book for grade 3.
November 14, 2025
I'll admit, it's fun to make fun of. It's fun to be like "But maybe all those people who never came back are actaully having so much fun in beautiful little village in the mountains of Obtuse", but as I said, it's fun.
These stories make fun read alouds and teach the math in an entertaining nad memorable way! Would defenatly recomend.
These stories make fun read alouds and teach the math in an entertaining nad memorable way! Would defenatly recomend.
November 24, 2025
Radius gets his turn in the spotlight for this third book, going on a quest to save King Lell from a labyrinth. He works solve the riddles that will lead him there, using a handy protractor-like family heirloom and lessons from his teacher, Sir D’Grees. Much more interesting than dry math lesson books.
September 14, 2025
This did not really address mathematics. As another reviewer posted, it is more of an exercise in vocabulary. The author really wanted to create a pun out of the story, so that is kinda what she did. But honestly, it falls short of what you would expect with the title.
October 6, 2018
Age: from 7 years old
Read
June 26, 2019Fictional Story
Math Concept: Anlges
Math Concept: Anlges
January 9, 2020
An exciting math adventure!
August 19, 2020
We love the Sir Cumference books, such witty and educational books about math!
November 26, 2020
I love this whole series! Originally bought them for my husband, who has a math & computer science background. They're really fabulous, and great tools for teaching math concepts as well.
February 23, 2022
One of the better stories in the series
March 4, 2022
Very good book teaching the angles of circles and triangle's. This cute little story is a good way to teach these mathamatical principles
March 5, 2022
This is a very nice little adventure book that teaches about angles.
June 10, 2022
One of the best.
July 7, 2022
Picture book, explaining angles in a very clever way. Recommended.
January 23, 2023
Who reads this garbage? My math teacher I’ll have a word about it!
September 22, 2023
This is probably our favorite in the Sir Cumference series, both for an exciting story and memorable explanations of angles.
December 31, 2024
Add this one to the list to read with children.
September 30, 2012
Grade/interest level: Upper Elementary
Reading level: AD450L (lexile.com)
Genre: Modern Fantasy/Science Fiction
Main Characters: Radius, Sir Cumference, Lady Di of Ameter, and Sir. D'Grees
Setting: Angleland
POV: third person, narrator
The Sir Cumference series uses a medieval fantasy setting to teach math concepts. For this book, Radius sets our to claim his knighthood by finding King Lell. In order to navigate the castle, Radius must discover the uses of his family heirloom (a protractor). Throughout his journey, he figures out how to make his knightly rights (right angles) and the degrees on the protractor in order to save the King.
This is a great learning resource for students who have emergent knowledge of geometry. It might be trickier for ESL students, but this book is an entertaining way to see real-life examples of various angles and learn how to use a protractor.
Reading level: AD450L (lexile.com)
Genre: Modern Fantasy/Science Fiction
Main Characters: Radius, Sir Cumference, Lady Di of Ameter, and Sir. D'Grees
Setting: Angleland
POV: third person, narrator
The Sir Cumference series uses a medieval fantasy setting to teach math concepts. For this book, Radius sets our to claim his knighthood by finding King Lell. In order to navigate the castle, Radius must discover the uses of his family heirloom (a protractor). Throughout his journey, he figures out how to make his knightly rights (right angles) and the degrees on the protractor in order to save the King.
This is a great learning resource for students who have emergent knowledge of geometry. It might be trickier for ESL students, but this book is an entertaining way to see real-life examples of various angles and learn how to use a protractor.
Displaying 1 - 30 of 92 reviews