Emily is having an ordinary day at Middletown Intermediate School. In Ms. Baldwin's class, she and her friends have just finished exploring the natural world in science class and are getting ready to learn about fractions when she gets distracted by a strange spot on her math paper. Emily discovers that the spot is actually person, shaped like the number one but with a face and a voice

It turns out this is Jackie, one of the Curious Ones. Emily takes Jackie's hand and goes on an exciting trip to the Land of Mathesis. There, Jackie and her brother, Jack, help Emily learn all about fractions. Simple addition expands into multiplication, and simple subtraction grows into division. Emily quickly builds her knowledge of fractions, learning about ratios and rates and how they are used in modeling the real world. Soon she discovers that math can be a lot of fun

This children's story follows a girl on a journey through a land of mathematics, where she learns all about fractions and how they are used.