Geometry is so much more than just naming shapes! It includes understanding 3D, reflection, polygons, and more. What better way to explore this curriculum topic than alongside a cute blue monster? Readers meet Mo who is also just starting to learn geometry. In each chapter, Mo learns about a new concept, and each chapter builds upon the knowledge presented earlier in the book. Diagrams and visual aids help readers--and Mo--through pyramids, patterns, and prisms, as they practice what they've learned in problems. A concluding answer key allows readers to check their work.