This is the third in a series of four reports describing a study of 1,614 junior high school mathematics and English students and 69 of their teachers that was undertaken to discover the effects of different teaching behaviors on cognitive and affective student outcomes. This booklet contains a discussion of different types of direct observation techniques, including their advantages and disadvantages; 12 scales for use in classroom observation, including definitions of the scales' behaviors and some examples; and a discussion of reliability data for the scales, including between-observer agreement and stability estimates. (TJ)