This document outlines 5 principles for the modern mathematics classroom: conjecture, communication, collaboration, chaos, and celebration. It discusses each principle in 1-2 paragraphs and provides examples. The principles emphasize wondering and questioning, explaining concepts simply, working together, engaging with non-routine problems, and acknowledging mistakes as learning opportunities. The overall message is that mathematics instruction should move away from rote memorization and toward active thinking, discussion, problem-solving, and an appreciation for the learning process.