Five Things I learned at TMC15: Thursday 7/23/15

1. Don’t give your students mathematical definitions. Instead, have groups of three or four students write a definition for a well-known mathematical idea or geometric figure on their own. Then, have each group pass their definition to the next group. Groups should now try to “break” their definitions by providing a counter example. Once they find a flaw in the definition, they refine the definition and continue passing the paper.

2. Here’s an idea for exit tickets. Make a grid with 3 by 3 inch boxes and write each of your student’s names in a different box. Place your grid on the wall near the door. Have your students complete their exit tickets on a sticky note, and stick them in their box on the grid as they leave class. This system makes it easy for students to hand in their exit slip and even easier for the teacher to grade. It is best used for reflective exit slips, as students could cheat on a skills-based or assessment-style exit slip.

3. Mathmistakes.org is a site is about compiling, analyzing and discussing the mathematical errors that students make. It is edited by Michael Pershan, a middle school and high school math teacher from NYC.

4. Manifold is an origami style game by The Incredible Company. It challenges players to take a small sheet of paper with scattered black and white boxes and fold it such that all the white boxes appear on one side and all the black boxes appear on the other. While it isn’t tied to any topic or standard, this is a fun activity in spatial reasoning that will either frustrate or leave you addicted.

5. Another game about spatial reasoning that will either frustrate or leave you addicted. Okay? is a simple iPad and iPhone app that challenges users to bounce a ball off a series of blocks in one shot. Best of all, you pay what you want for this app.

6. (Extra Credit) Dueling Piano bars are the best.