This document discusses guiding principles for classroom observation from Sullivan and Glanz (2000). It outlines 10 principles: 1) observation requires reflective discussion, 2) instruments provide data to help teachers improve, 3) observation involves factual descriptions and interpretations, 4) conclusions should be based on observed behaviors, 5) supervisors and teachers should collaboratively choose instruments, 6) personal biases can impact interpretations, 7) observation is a skill developed over time, 8) not all behaviors can be observed, 9) feedback is essential, and 10) multiple observations are needed to capture different aspects.