Matt, Bibi, and their dog Riley crawled through the tiny opening first. FWUMP! A secret door suddenly closed behind them . . . The Zills family is summoned to Egypt to help find the hidden burial chamber of an ancient pharaoh. But when Matt and Bibi get trapped in the pharaoh's pyramid, they stumble upon an even bigger mystery. With only each other, their dog Riley, and the geometric hieroglyphics on the walls to help them, the twins must use their math skills to locate the burial chamber-and the way out. Luckily, Matt and Bibi know their stuff when it comes to geometric solids, and so will the readers of this adventure in math!

Join Sir Cumference and the gang for more wordplay, puns, and problem solving in the clever math adventure about place-value and counting by tens. Sir Cumference and Lady Di planned a surprise birthday party for King Arthur, but they didn’t expect so many guests to show up. How many lunches will they need? And with more guests arriving by the minute, what about dinner? Sir Cumference and Lady Di count guests by tens, hundreds, and even thousands to help young readers learn place-value. Fans will love this new installment of the Sir Cumference series that makes math fun and accessible for all.

Medieval math favorite Sir Cumference series is back! Lady Di of Ameter and Percilla Centwell figure out parts of a whole in this fun percent introduction. Percilla Centwell and Lady Di are off to Gaggleston-on-Green to deliver Percilla's flock of one hundred geese to the townspeople who ordered them. When some of the geese go missing on the way, Percilla and Lady Di must figure out a way to make sure all of the customers still get their fair share of the flock. In this latest medieval math adventure, readers learn about finding percents as part of a whole by using fractions. The endnote includes step-by-step instructions for calculating percent.

Join Sir Cumference, Lady Di of Ameter, and their son Radius for wordplay, puns, and problem solving in this geometry-packed math adventure. King Arthur was a good ruler, but now he needs a good ruler. What would you do if the neighboring kingdom were threatening war? Naturally, you'd call your strongest and bravest knights together to come up with a solution. But when your conference table causes more problems than the threat of your enemy, you need expert help. Enter Sir Cumference, his wife Lady Di of Ameter, and their son Radius. With the help of the carpenter, Geo of Metry, this sharp-minded team designs the perfect table conducive to discussing the perfect plan for peace. The first in Sir Cumference series, SIR CUMFERENCE AND THE FIRST ROUND TABLE makes math fun and accessible for everyone.

Join Sir Cumference, Lady Di of Ameter, and their son Radius for wordplay, puns, and problem solving in this geometry-packed math adventure. King Arthur was a good ruler, but now he needs a good ruler. What would you do if the neighboring kingdom were threatening war? Naturally, you'd call your strongest and bravest knights together to come up with a solution. But when your conference table causes more problems than the threat of your enemy, you need expert help. Enter Sir Cumference, his wife Lady Di of Ameter, and their son Radius. With the help of the carpenter, Geo of Metry, this sharp-minded team designs the perfect table conducive to discussing the perfect plan for peace. The first in Sir Cumference series, SIR CUMFERENCE AND THE FIRST ROUND TABLE makes math fun and accessible for everyone.

For fans of the Sir Cumference series with Pi on their mind, here is the second installment in this fun look at math and language. This time the math adventure is centered around a potion that changes Sir Cumference into a fire-breathing dragon. Can Radius change him back? Join Radius on his quest through the castle to solve a riddle that will reveal the cure. It lies in discovering the magic number that is the same for all circles. Perfect for parent and teachers who are looking to make math fun and accessible for everyone.

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. With a medallion at the back of the book readers can jump in the adventure and help Radius find the right angle.

Join Sir Cumference and the gang for more wordplay, puns, and problem solving in the clever math adventure that introduces readers to  charts and graphs through an annual bake-off. Sir Cumference and Lady Di need a baker to prepare a special dessert for the annual Harvest Faire. Two bakers compete to see whose dessert is most popular. When Pia of Chartres and Bart Graf have trouble keeping track of the votes their desserts receive, they each develop a better system. Pia places a colored candy around the edges of a pie dough (like a pie chart), and Bart stacks up cookie tins (making a 3D bar graph). When there's a tie, the two chefs cook up a hybrid dessert just in time for the Faire. Puns--both literal and visual--abound in this fun adventure story with beloved characters and a solid pedagogical foundation.

Join Sir Cumference and the gang for more wordplay, puns, and problem solving in the clever math adventure that introduces readers to the concept of rounding numbers. When Steward Edmund Rounds and Sir Cumference notice that there are strangers camped nearby, Rounds II decides to investigate despite being involved with the task of learning how to make accurate counts of the castle's stores of food, supplies, and weaponry. When he reports back that an enemy is lying in wait, everyone moves quickly to defend the castle. But wait! Will Rounds II be able to figure out how many bows and arrows they have to create an appropriate battle plan? Using rounding techniques to figure out the totals more quickly, Rounds II is just in time to help stave off a potentially disastrous attack. Readers will love making the rounds with Rounds II and the gang in this new installment of the Sir Cumference series that makes math fun and accessible for all.

Join Sir Cumference and the gang for more wordplay, puns, and problem solving in the clever math adventure that introduces readers to the concept of rounding numbers. When Steward Edmund Rounds and Sir Cumference notice that there are strangers camped nearby, Rounds II decides to investigate despite being involved with the task of learning how to make accurate counts of the castle's stores of food, supplies, and weaponry. When he reports back that an enemy is lying in wait, everyone moves quickly to defend the castle. But wait! Will Rounds II be able to figure out how many bows and arrows they have to create an appropriate battle plan? Using rounding techniques to figure out the totals more quickly, Rounds II is just in time to help stave off a potentially disastrous attack. Readers will love making the rounds with Rounds II and the gang in this new installment of the Sir Cumference series that makes math fun and accessible for all.

A funny and pun-filled retelling of “The Sword and Stone” that introduces readers to mathematical angles. King Arthur has hidden his sword, Edgecalibur and issued a challenge to the knights. The first knight to find the sword will be the next king. Can Sir Cumference and Lady Di point Radius's best friend, Vertex in the right direction? Will Vertex's sharp thinking give him the edge? Join Sir Cumference, Lady Di of Ameter, and their son, Radius, in this new adventure where they race to help Vertex find the sword and discover the secrets of cubes, pyramids, cylinders, and cones.

For fans of the Sir Cumference series with coordinate geometry on their mind, here is the seventh installment in this fun look at math and language. While riding through the forests of Angleland, cousins Per and Radius realize they are lost and are desperate for a map to guide them home. Soon they come across a mysterious house in the hills. Inside they find a map to a treasure belonging to Xaxon Yellowbearyd, the fiercest Viking warrior of his time. Per and Radius must decode the strange numbered grid on the map, while trying to steer clear of the pack of bungling bandits who are on their tail. Will they find the treasure in time? Cindy Neuschwander delivers yet another intriguing math adventure featuring the well-known characters of Angleland. Readers will enjoy following Per and Radius in their quest while learning how coordinate geometry relates to everyday life. Wayne Geehan’s beautiful illustrations offer a bit of comic relief, while also clearly demonstrating the concepts explored in the story.

For fans of the Sir Cumference series with coordinate geometry on their mind, here is the seventh installment in this fun look at math and language. While riding through the forests of Angleland, cousins Per and Radius realize they are lost and are desperate for a map to guide them home. Soon they come across a mysterious house in the hills. Inside they find a map to a treasure belonging to Xaxon Yellowbearyd, the fiercest Viking warrior of his time. Per and Radius must decode the strange numbered grid on the map, while trying to steer clear of the pack of bungling bandits who are on their tail. Will they find the treasure in time? Cindy Neuschwander delivers yet another intriguing math adventure featuring the well-known characters of Angleland. Readers will enjoy following Per and Radius in their quest while learning how coordinate geometry relates to everyday life. Wayne Geehan’s beautiful illustrations offer a bit of comic relief, while also clearly demonstrating the concepts explored in the story.

Part of the popular Sir Cumference series! Baker Pia is back with a handy way of counting by tens and fractions in this fun introduction to the decimal system. This time the focus is back on Pia of Chartres from Sir Cumference and the Off-the-Charts Dessert. She is kidnapped by a family of ogres--Tentt, the father, Hoondrit, the mother, and their ten daughters, Una to Decima. Pia is asked to help the ogres prepare a feast for a large celebration, which will involve tens, hundreds, even thousands of pieces of dessert! Readers will learn about place value and the decimal system of notation in this latest medieval math adventure. The endnote includes a diagram with place names.

Part of the popular Sir Cumference series! Baker Pia is back with a handy way of counting by tens and fractions in this fun introduction to the decimal system. This time the focus is back on Pia of Chartres from Sir Cumference and the Off-the-Charts Dessert. She is kidnapped by a family of ogres--Tentt, the father, Hoondrit, the mother, and their ten daughters, Una to Decima. Pia is asked to help the ogres prepare a feast for a large celebration, which will involve tens, hundreds, even thousands of pieces of dessert! Readers will learn about place value and the decimal system of notation in this latest medieval math adventure. The endnote includes a diagram with place names.