One equals zero! Every number is greater than itself! All triangles are isosceles! Surprised? Welcome to the world of One Equals Zero and Other Mathematical Surprises. In this engaging book of blackline activity masters, all men are bald, mistakes are lucky, and teachers can never spring surprise tests on their students!

Each paradox, fallacy, and mind boggler in One Equals Zero will challenge high school students at any grade level, encourage them to look at familiar mathematical situations in a new light, and help them better understand both the possibilities and the limitations of mathematics.

• Many of the paradoxes, fallacies, and mind bogglers in One Equals Zero are based on classic paradoxes and can be used in algebra, geometry, trigonometry, statistics, or calculus classes.
• One- and two-page activities can be used to reinforce, refine, or clarify a concept your students are studying, to add an element of surprise to your mathematics, to stimulate problem-solving skills, and as discussion topics and extra-credit assignments. Most of the activities can be completed in less than one class period and require no additional materials.
• Detailed teacher's notes accompanying each activity provide a thorough explanation of the paradox or problem; in-depth pedagogical and mathematical comments; suggestions for extensions; and, for many activities, related historical material.
• A matrix of key concepts at the beginning of the book allows you to easily place each activity in a suitable context. Key concepts are also included in the teacher's notes for each activity.
• A list of recommended reading guides you and your students to a wealth of related material.

With One Equals Zero, you can transform mathematical errors and quandaries into positive learning experiences. Along the way you'll encourage your students to see that the development of mathematical skill is a process of creative struggle and spirited debate.