This observer training manual was developed as a central component of a research effort, Changing Teacher Practice (CTP), which was designed to increase the frequency of effective teaching behaviors and staff development strategies in an ongoing school system. The observations focused on two major aspects of classroom teaching--instruction and classroom organization. After an introduction, an overview of the observation process is presented. Four sections provide guidelines for each component of observation: (1) the Barnes Teacher Observation Instrument (BTOI); (2) the Observation Record; (3) the Summary Paragraph; and (4) the Student Engagement Ratings (SER) form. Appendices include a guide for classroom protocol, a list of concepts and terms, a table of random numbers for use with SER forms, a brief description on the observer training, examples of the completed forms, the research basis for the BTOI, and a checklist for observations. (JD)