The aim of this chapter is to show teachers how to observe students and their work in ways that enhance the development of new teaching strategies. Daily classroom observations are an important source of data for teachers. Observations of students can provide insight into discovering the causes of unexpected patterns of student behavior. More specifically, they can indicate the level of student involvement, the degree to which students are involved in higher level thinking, and the quality of student interactions. Methods of observation can range from open-ended queries to checklists of targeted student behaviors. Examples would include observing students while completing a task, while talking in groups, while working on a project, or while performing a skill. Student work can also be examined by noting strengths or weaknesses in student writing, student tests, and patterns of student problem solving. Finally, student talk can also be studied to determine response patterns, as well as the quantity and quality of student interactions.