By way of introduction, Cheng writes:

“When you think about math, what do you think about? Do you think it’s all just numbers and equations? Then think again…

Math is really about exploring ideas and using our imagination. It’s a way of making sense of the world - or of making seemingly impossible things possible!”

A little girl named Molly receives a note asking her on an adventure and readers are invited to accompany her. Molly steps through a window and everything in her world is inside out, or the opposite of what is expected. Cheng uses this upside-down world to explain that there are many such opposites, or inverses in math, such as multiplication versus division, and adding versus subtraction.

Molly continues to explore with the help of detailed pictures with die-cut flaps and doors and text boxes that explain what she is seeing and how it works. She first sees “The Impossible Staircase,” then a garden of hidden shapes, a hall of endless doors, a room full of pipes and vents from which she has to escape, a room full of carpets make from Latin squares, a mixed-up library, and so on. In each room, Molly has to figure out what is going on and how to get to the next adventure. In the process, she, along with readers, learns about mathematical concepts like symmetry and fractals and different dimensions.

Finally Molly wakes up from what was a dream, but “Molly’s head is full of patterns, shapes, and impossible objects.”

The author concludes with a few pages with more information about math, expanding on the ideas introduced during Molly’s adventure.

Illustrator Aleksandra Artymowska provides fun colorful and detailed illustrations to give a range of readers starting at age 6 and over plenty to explore.

Evaluation:. This book will give adults a great opportunity to convince reluctant students that math is fascinating and fun. ( )

There are many math concepts introduced in this book, but none of them are detailed enough to introduce a topic alone. ( )