Math Magic Trick

This trick is an extraordinary introduction to the power of algebraic thinking, and a reminder of what makes algebra so awe-inspiring. A video Launch for this lesson is available in two parts. PDF of the lesson is below the videos. Part 1. When using as a class launch, stop at 2:45 and let the class come up try to find …

Counterexamples

Topics: logic, deduction, mathematical argument, communication Materials: None Recommended Grades: K, 1, 2, 3, 4, 5, 6, 7, 8 Common Core: Variable, but especially MP3 Proving the teacher wrong. Rigorously. Why We Love Counterexamples Every kid loves to prove the teacher wrong. With Counterexamples, they get to do this in a productive way, and learn appropriate mathematical skepticism and communication …